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3 months ago

Scientists believe they've found evidence of what was once an ocean on Mars. Check out the shoreline on mars!

Scientists Believe They've Found Evidence Of What Was Once An Ocean On Mars. Check Out The Shoreline

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11 months ago

have you seen the JWST images of the pillars of creation? i could cry just looking at them. they’re so beautiful.

looking at them i get so emotional. i can’t believe i am lucky enough to be alive in this time of beginning to understand the cosmos.

Have You Seen The JWST Images Of The Pillars Of Creation? I Could Cry Just Looking At Them. They’re

(second half has been rotated to match orientation of the first)

once i am well enough i will be going to college for astrophysics. i cannot wait to be who i know i can be.


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1 year ago

Black Scientists and Engineers Past and Present Enable NASA Space Telescope

The Nancy Grace Roman Space Telescope is NASA’s next flagship astrophysics mission, set to launch by May 2027. We’re currently integrating parts of the spacecraft in the NASA Goddard Space Flight Center clean room.

Once Roman launches, it will allow astronomers to observe the universe like never before. In celebration of Black History Month, let’s get to know some Black scientists and engineers, past and present, whose contributions will allow Roman to make history.

Black woman sitting in front of a camera that is slightly off-frame. She is wearing a brown sweater with a white collared shirt underneath. There are images of Earth from space behind her. Credit: NASA

Dr. Beth Brown

The late Dr. Beth Brown worked at NASA Goddard as an astrophysicist. in 1998, Dr. Brown became the first Black American woman to earn a Ph.D. in astronomy at the University of Michigan. While at Goddard, Dr. Brown used data from two NASA X-ray missions – ROSAT (the ROentgen SATellite) and the Chandra X-ray Observatory – to study elliptical galaxies that she believed contained supermassive black holes.  

With Roman’s wide field of view and fast survey speeds, astronomers will be able to expand the search for black holes that wander the galaxy without anything nearby to clue us into their presence.

Black-and-white photograph of a Black man standing in front of a chalkboard. He is wearing a dark-colored blazer with a light-colored collared button-up underneath. Credit: courtesy of ​​Georgetown University Archives

Dr. Harvey Washington Banks 

In 1961, Dr. Harvey Washington Banks was the first Black American to graduate with a doctorate in astronomy. His research was on spectroscopy, the study of how light and matter interact, and his research helped advance our knowledge of the field. Roman will use spectroscopy to explore how dark energy is speeding up the universe's expansion.

A Black woman stands with her back to the camera and is looking over her shoulder. She is wearing a dark blue jacket that has a white circle outlined image of a plane and the word NASA underneath. She is standing in front of a giant metal circular ring. It sits inside of a large black square box. Credit: NASA/Sydney Rohde

NOTE - Sensitive technical details have been digitally obscured in this photograph. 

Sheri Thorn 

Aerospace engineer Sheri Thorn is ensuring Roman’s primary mirror will be protected from the Sun so we can capture the best images of deep space. Thorn works on the Deployable Aperture Cover, a large, soft shade known as a space blanket. It will be mounted to the top of the telescope in the stowed position and then deployed after launch. Thorn helped in the design phase and is now working on building the flight hardware before it goes to environmental testing and is integrated to the spacecraft.

A smiling Black woman with shoulder-length straight black hair, glasses, and a white lab coat sits at a blue desk, holding a green circuit board in each hand. She is in a laboratory, and shelves with computer monitors and wires sit behind and around her. A sheet of shiny silver metal stands behind her head, and bags of wires and parts are visible on the desk beside her. Credit: NASA/Katy Comber

Sanetra Bailey 

Roman will be orbiting a million miles away at the second Lagrange point, or L2. Staying updated on the telescope's status and health will be an integral part of keeping the mission running. Electronics engineer Sanetra Bailey is the person who is making sure that will happen. Bailey works on circuits that will act like the brains of the spacecraft, telling it how and where to move and relaying information about its status back down to Earth.  

 Learn more about Sanetra Bailey and her journey to NASA. 

A Black man in a clean room wearing a clean suit covering his whole body except his eyes, wearing blue gloves, and holding up a flight detector. Credit: NASA/ Chris Gunn

Dr. Gregory Mosby 

Roman’s field of view will be at least 100 times larger than the Hubble Space Telescope's, even though the primary mirrors are the same size. What gives Roman the larger field of view are its 18 detectors. Dr. Gregory Mosby is one of the detector scientists on the Roman mission who helped select the flight detectors that will be our “eyes” to the universe.

Dr. Beth Brown, Dr. Harvey Washington Banks, Sheri Thorn, Sanetra Bailey, and Dr. Greg Mosby are just some of the many Black scientists and engineers in astrophysics who have and continue to pave the way for others in the field. The Roman Space Telescope team promises to continue to highlight those who came before us and those who are here now to truly appreciate the amazing science to come. 

A simulated space image with the Roman Space Telescope at the center. It heads toward a purple-and-pink galaxy, and you can see down the barrel opening of the spacecraft. Credit: NASA

To stay up to date on the mission, check out our website and follow Roman on X and Facebook.

Make sure to follow us on Tumblr for your regular dose of space!


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1 year ago
Many thousands of bright stars speckle the screen. The smallest ones are white pinpoints, strewn across the screen like spilled salt. Larger ones are yellow and bluish white with spiky outer edges like sea urchins. Credit: Matthew Penny (Louisiana State University)

A simulated image of NASA’s Nancy Grace Roman Space Telescope’s future observations toward the center of our galaxy, spanning less than 1 percent of the total area of Roman’s Galactic Bulge Time-Domain Survey. The simulated stars were drawn from the Besançon Galactic Model.

Exploring the Changing Universe with the Roman Space Telescope

The view from your backyard might paint the universe as an unchanging realm, where only twinkling stars and nearby objects, like satellites and meteors, stray from the apparent constancy. But stargazing through NASA’s upcoming Nancy Grace Roman Space Telescope will offer a front row seat to a dazzling display of cosmic fireworks sparkling across the sky.

Roman will view extremely faint infrared light, which has longer wavelengths than our eyes can see. Two of the mission’s core observing programs will monitor specific patches of the sky. Stitching the results together like stop-motion animation will create movies that reveal changing objects and fleeting events that would otherwise be hidden from our view.

Watch this video to learn about time-domain astronomy and how time will be a key element in NASA’s Nancy Grace Roman Space Telescope’s galactic bulge survey. Credit: NASA’s Goddard Space Flight Center

This type of science, called time-domain astronomy, is difficult for telescopes that have smaller views of space. Roman’s large field of view will help us see huge swaths of the universe. Instead of always looking at specific things and events astronomers have already identified, Roman will be able to repeatedly observe large areas of the sky to catch phenomena scientists can't predict. Then astronomers can find things no one knew were there!

One of Roman’s main surveys, the Galactic Bulge Time-Domain Survey, will monitor hundreds of millions of stars toward the center of our Milky Way galaxy. Astronomers will see many of the stars appear to flash or flicker over time.

This animation illustrates the concept of gravitational microlensing. When one star in the sky appears to pass nearly in front of another, the light rays of the background source star are bent due to the warped space-time around the foreground star. The closer star is then a virtual magnifying glass, amplifying the brightness of the background source star, so we refer to the foreground star as the lens star. If the lens star harbors a planetary system, then those planets can also act as lenses, each one producing a short change in the brightness of the source. Thus, we discover the presence of each exoplanet, and measure its mass and how far it is from its star. Credit: NASA's Goddard Space Flight Center Conceptual Image Lab 

That can happen when something like a star or planet moves in front of a background star from our point of view. Because anything with mass warps the fabric of space-time, light from the distant star bends around the nearer object as it passes by. That makes the nearer object act as a natural magnifying glass, creating a temporary spike in the brightness of the background star’s light. That signal lets astronomers know there’s an intervening object, even if they can’t see it directly.

A galaxy with a large, warmly glowing circular center and several purplish spiral arms extending outward, wrapped around the center like a cinnamon roll. Stars speckle the entire galaxy, but they are most densely packed near the center where they're yellower. Toward the outer edges, the stars are whiter. Overlaid on top of the galaxy is a small pink outline of a spacecraft located a little more than halfway out toward the bottom edge of the galaxy. A reddish search beam extends across the galaxy through its center, about to the same point on the opposite side. Credit: NASA’s Goddard Space Flight Center/CI Lab

This artist’s concept shows the region of the Milky Way NASA’s Nancy Grace Roman Space Telescope’s Galactic Bulge Time-Domain Survey will cover – relatively uncharted territory when it comes to planet-finding. That’s important because the way planets form and evolve may be different depending on where in the galaxy they’re located. Our solar system is situated near the outskirts of the Milky Way, about halfway out on one of the galaxy’s spiral arms. A recent Kepler Space Telescope study showed that stars on the fringes of the Milky Way possess fewer of the most common planet types that have been detected so far. Roman will search in the opposite direction, toward the center of the galaxy, and could find differences in that galactic neighborhood, too.

Using this method, called microlensing, Roman will likely set a new record for the farthest-known exoplanet. That would offer a glimpse of a different galactic neighborhood that could be home to worlds quite unlike the more than 5,500 that are currently known. Roman’s microlensing observations will also find starless planets, black holes, neutron stars, and more!

This animation shows a planet crossing in front of, or transiting, its host star and the corresponding light curve astronomers would see. Using this technique, scientists anticipate NASA’s Nancy Grace Roman Space Telescope could find 100,000 new worlds. Credit: NASA’s Goddard Space Flight Center/Chris Smith (USRA/GESTAR)

Stars Roman sees may also appear to flicker when a planet crosses in front of, or transits, its host star as it orbits. Roman could find 100,000 planets this way! Small icy objects that haunt the outskirts of our own solar system, known as Kuiper belt objects, may occasionally pass in front of faraway stars Roman sees, too. Astronomers will be able to see how much water the Kuiper belt objects have because the ice absorbs specific wavelengths of infrared light, providing a “fingerprint” of its presence. This will give us a window into our solar system’s early days.

A fiery orange globe appears at the left of a white disk of spinning material. As the disk spins, it draws material from the orange globe. Then suddenly the center of the white disk grows extremely bright as a sphere of white blossoms outward. The explosive white sphere then expands, quickly encompassing the whole screen in white criss-crossed with purplish gray filaments. Credit: NASA’s Goddard Space Flight Center/CI

This animation visualizes a type Ia supernova.

Roman’s High Latitude Time-Domain Survey will look beyond our galaxy to hunt for type Ia supernovas. These exploding stars originate from some binary star systems that contain at least one white dwarf – the small, hot core remnant of a Sun-like star. In some cases, the dwarf may siphon material from its companion. This triggers a runaway reaction that ultimately detonates the thief once it reaches a specific point where it has gained so much mass that it becomes unstable.

NASA’s upcoming Nancy Grace Roman Space Telescope will see thousands of exploding stars called supernovae across vast stretches of time and space. Using these observations, astronomers aim to shine a light on several cosmic mysteries, providing a window onto the universe’s distant past. Credit: NASA’s Goddard Space Flight Center

Since these rare explosions each peak at a similar, known intrinsic brightness, astronomers can use them to determine how far away they are by simply measuring how bright they appear. Astronomers will use Roman to study the light of these supernovas to find out how quickly they appear to be moving away from us.

By comparing how fast they’re receding at different distances, scientists can trace cosmic expansion over time. This will help us understand whether and how dark energy – the unexplained pressure thought to speed up the universe’s expansion – has changed throughout the history of the universe.

Left of center, two bright blue circular shapes appear to be joined toward the center of the frame. They are whitest on their outermost edges. Debris, also white and bright blue, emanates outward and extends all around the frame. The background is black. Credit: NASA, ESA, J. Olmsted (STScI)

NASA’s Nancy Grace Roman Space Telescope will survey the same areas of the sky every few days. Researchers will mine this data to identify kilonovas – explosions that happen when two neutron stars or a neutron star and a black hole collide and merge. When these collisions happen, a fraction of the resulting debris is ejected as jets, which move near the speed of light. The remaining debris produces hot, glowing, neutron-rich clouds that forge heavy elements, like gold and platinum. Roman’s extensive data will help astronomers better identify how often these events occur, how much energy they give off, and how near or far they are.

And since this survey will repeatedly observe the same large vista of space, scientists will also see sporadic events like neutron stars colliding and stars being swept into black holes. Roman could even find new types of objects and events that astronomers have never seen before!

Learn more about the exciting science Roman will investigate on X and Facebook.

Make sure to follow us on Tumblr for your regular dose of space!


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1 year ago

Black Hole Friday Deals!

Ad-style comic titled “Black Hole Friday Sales.” Middle of the page “Out-of-this-world deals!” Scattered throughout are illustrated “coupons.” From top to bottom, the taglines read: “Free travel guide to planning your next black hole vacation (when you purchase a cosmic timeshare)”; “Add some planets to your system with this exoplanet bundle!”; “Accretion disk skirt: Be the center of attention. Made of 100% recycled material”; “Standard candles: Reliably bright. Non-scented. Long-lasting burn”; Stephan’s Quintet: A 5-for-1 galactic deal”; “Black hole merger: Get ready to ride this (gravitational) wave before this deal ends”; “Widow system: Act quickly before these stars disappear!”; “Black holes: the perfect (permanent) storage solution”; “Spaghettify! Noodles: Feed the black hole of your stomach”; and “Ready Space Player One. Limited time offer: Roman Space Observer Black Hole DLC! This weekend only!” At the bottom “Get these deals before they disappear beyond the point of no return."

Get these deals before they are sucked into a black hole and gone forever! This “Black Hole Friday,” we have some cosmic savings that are sure to be out of this world.

Your classic black holes — the ultimate storage solution.

Galactic 5-for-1 special! Learn more about Stephan’s Quintet.

Limited-time offer game DLC! Try your hand at the Roman Space Observer Video Game, Black Hole edition, available this weekend only.

Standard candles: Exploding stars that are reliably bright. Multi-functional — can be used to measure distances in space!

Feed the black hole in your stomach. Spaghettification’s on the menu.

Act quickly before the stars in this widow system are gone!

Add some planets to your solar system! Grab our Exoplanet Bundle.

Get ready to ride this (gravitational) wave before this Black Hole Merger ends!

Be the center of attention in this stylish accretion disk skirt. Made of 100% recycled cosmic material.

Should you ever travel to a black hole? No. But if you do, here’s a free guide to make your trip as safe* as possible. *Note: black holes are never safe. 

Make sure to follow us on Tumblr for your regular dose of space!


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1 year ago
Vibrantly hued shapes speckle an image with a black background. Orbs glowing red, yellow, and blue are strewn across the frame, and a large, translucent blue haze dominates most of the center. Credit: NASA, ESA, and M. Brodwin (University of Missouri)

Astronomers used three of NASA's Great Observatories to capture this multiwavelength image showing galaxy cluster IDCS J1426.5+3508. It includes X-rays recorded by the Chandra X-ray Observatory in blue, visible light observed by the Hubble Space Telescope in green, and infrared light from the Spitzer Space Telescope in red. This rare galaxy cluster has important implications for understanding how these megastructures formed and evolved early in the universe.

How Astronomers Time Travel

Let’s add another item to your travel bucket list: the early universe! You don’t need the type of time machine you see in sci-fi movies, and you don’t have to worry about getting trapped in the past. You don’t even need to leave the comfort of your home! All you need is a powerful space-based telescope.

But let’s start small and work our way up to the farthest reaches of space. We’ll explain how it all works along the way.

This animation shows a small, blue planet Earth at the left of the frame and an even smaller white dot representing the Moon at the right. The background is black. A beam of light travels back and forth between them. The graphic is labeled “Earth and Moon to scale, Speed of light in real-time, surface-to-surface in 1.255 seconds, average distance 384,400 km.” Credit: James O'Donoghue, used with permission

This animation illustrates how fast light travels between Earth and the Moon. The farther light has to travel, the more noticeable its speed limit becomes.

The speed of light is superfast, but it isn’t infinite. It travels at about 186,000 miles (300 million meters) per second. That means that it takes time for the light from any object to reach our eyes. The farther it is, the more time it takes.

You can see nearby things basically in real time because the light travel time isn’t long enough to make a difference. Even if an object is 100 miles (161 kilometers) away, it takes just 0.0005 seconds for light to travel that far. But on astronomical scales, the effects become noticeable.

The Sun and planets are lined up along the center of the frame with distances shown to scale. The title is “The Solar System: with real-time speed of light.” Earth is labeled 1 AU, 8 minutes 17 seconds; Jupiter is 5.2 AU, 43 minutes 17 seconds; Saturn is 9.6 AU, 1 hour 20 minutes; Uranus is 19.2 AU, 2 hours 40 minutes; and Neptune is 30 AU, 4 hours 10 minutes. The bottom of the graphic says, “1 AU (astronomical unit) = 93 million miles, or 150 million kilometers.” Credit: James O'Donoghue, used with permission

This infographic shows how long it takes light to travel to different planets in our solar system.

Within our solar system, light’s speed limit means it can take a while to communicate back and forth between spacecraft and ground stations on Earth. We see the Moon, Sun, and planets as they were slightly in the past, but it's not usually far enough back to be scientifically interesting.

As we peer farther out into our galaxy, we use light-years to talk about distances. Smaller units like miles or kilometers would be too overwhelming and we’d lose a sense of their meaning. One light-year – the distance light travels in a year – is nearly 6 trillion miles (9.5 trillion kilometers). And that’s just a tiny baby step into the cosmos.

The Sun’s closest neighboring star, Proxima Centauri, is 4.2 light-years away. That means we see it as it was about four years ago. Betelgeuse, a more distant (and more volatile) stellar neighbor, is around 700 light-years away. Because of light’s lag time, astronomers don’t know for sure whether this supergiant star is still there! It may have already blasted itself apart in a supernova explosion – but it probably has another 10,000 years or more to go.

An undulating, translucent star-forming region in the Carina Nebula, hued in ambers and blues. Foreground stars with diffraction spikes can be seen, as can a speckling of background points of light through the cloudy nebula. Credit: NASA, ESA, CSA, and STScI

What looks much like craggy mountains on a moonlit evening is actually the edge of a nearby, young, star-forming region NGC 3324 in the Carina Nebula. Captured in infrared light by the Near-Infrared Camera (NIRCam) on NASA’s James Webb Space Telescope, this image reveals previously obscured areas of star birth.

The Carina Nebula clocks in at 7,500 light-years away, which means the light we receive from it today began its journey about 3,000 years before the pyramids of Giza in Egypt were built! Many new stars there have undoubtedly been born by now, but their light may not reach Earth for thousands of years.

Glowing spiral arms are twisted around like a cosmic cinnamon roll. A bright yellow oval is diagonal in the center of the frame, and sprays of stars extend outward from it like tentacles. Pink, white, and blue stars speckle the spiral arms and dusty lanes lie in between. The glowing arms are streaked with smaller clumps of dust. Credit: NASA and Nick Risinger

An artist’s concept of our Milky Way galaxy, with rough locations for the Sun and Carina nebula marked.

If we zoom way out, you can see that 7,500 light-years away is still pretty much within our neighborhood. Let’s look further back in time…

Spiral galaxy NGC 5643 with a bright, barred center surrounded by an orange-y glow. Vaguely purplish swirling arms extend outward from the center and appear somewhat mottled as streams of dust block white and blue stars in the arms here and there. A few stars are each surrounded by many sharp diffraction spikes. Credit: ESA/Hubble and NASA, A. Riess et al.; acknowledgement: Mahdi Zamani

This stunning image by the NASA/ESA Hubble Space Telescope features the spiral galaxy NGC 5643. Looking this good isn’t easy; 30 different exposures, for a total of nine hours of observation time, together with Hubble’s high resolution and clarity, were needed to produce an image of such exquisite detail and beauty.

Peering outside our Milky Way galaxy transports us much further into the past. The Andromeda galaxy, our nearest large galactic neighbor, is about 2.5 million light-years away. And that’s still pretty close, as far as the universe goes. The image above shows the spiral galaxy NGC 5643, which is about 60 million light-years away! That means we see it as it was about 60 million years ago.

As telescopes look deeper into the universe, they capture snapshots in time from different cosmic eras. Astronomers can stitch those snapshots together to unravel things like galaxy evolution. The closest ones are more mature; we see them nearly as they truly are in the present day because their light doesn’t have to travel as far to reach us. We can’t rewind those galaxies (or our own), but we can get clues about how they likely developed. Looking at galaxies that are farther and farther away means seeing these star cities in ever earlier stages of development.

The farthest galaxies we can see are both old and young. They’re billions of years old now, and the light we receive from them is ancient since it took so long to traverse the cosmos. But since their light was emitted when the galaxies were young, it gives us a view of their infancy.

The animation begins with a tiny dot of purplish light which quickly explodes, with a flash of light blossoming out to cover the whole frame. The light subsides and the screen shows galaxies of smudgy or spiral shapes racing outward from the center of the frame. Credit: NASA’s Goddard Space Flight Center

This animation is an artist’s concept of the big bang, with representations of the early universe and its expansion.

Comparing how fast objects at different distances are moving away opened up the biggest mystery in modern astronomy: cosmic acceleration. The universe was already expanding as a result of the big bang, but astronomers expected it to slow down over time. Instead, it’s speeding up!

The universe’s expansion makes it tricky to talk about the distances of the farthest objects. We often use lookback time, which is the amount of time it took for an object’s light to reach us. That’s simpler than using a literal distance, because an object that was 10 billion light-years away when it emitted the light we received from it would actually be more than 16 billion light-years away right now, due to the expansion of space. We can even see objects that are presently over 30 billion light-years from Earth, even though the universe is only about 14 billion years old.

Hundreds of red, yellow, white, and blue galaxies are sprinkled across a black background, appearing as small, brightly colored smudges. The tiniest galaxies appear as mere dots, while larger ones are disk-shaped. One blue star with six diffraction spikes shines in the lower-left corner. Credit: NASA, ESA, CSA, and M. Zamani (ESA/Webb). Science: B. Robertson (UCSC), S. Tacchella (Cambridge), E. Curtis-Lake (Hertfordshire), S. Carniani (Scuola Normale Superiore), and the JADES Collaboration

This James Webb Space Telescope image shines with the light from galaxies that are more than 13.4 billion years old, dating back to less than 400 million years after the big bang.

Our James Webb Space Telescope has helped us time travel back more than 13.4 billion years, to when the universe was less than 400 million years old. When our Nancy Grace Roman Space Telescope launches in a few years, astronomers will pair its vast view of space with Webb’s zooming capabilities to study the early universe in better ways than ever before. And don’t worry – these telescopes will make plenty of pit stops along the way at other exciting cosmic destinations across space and time.

Learn more about the exciting science Roman will investigate on X and Facebook.

Make sure to follow us on Tumblr for your regular dose of space!


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2 years ago

Caution: Universe Work Ahead 🚧

We only have one universe. That’s usually plenty – it’s pretty big after all! But there are some things scientists can’t do with our real universe that they can do if they build new ones using computers.

The universes they create aren’t real, but they’re important tools to help us understand the cosmos. Two teams of scientists recently created a couple of these simulations to help us learn how our Nancy Grace Roman Space Telescope sets out to unveil the universe’s distant past and give us a glimpse of possible futures.

Caution: you are now entering a cosmic construction zone (no hard hat required)!

A black square covered in thousands of tiny red dots and thousands more slightly larger, white and yellow fuzzy blobs. Each speck is a simulated galaxy. Credit: M. Troxel and Caltech-IPAC/R. Hurt

This simulated Roman deep field image, containing hundreds of thousands of galaxies, represents just 1.3 percent of the synthetic survey, which is itself just one percent of Roman's planned survey. The full simulation is available here. The galaxies are color coded – redder ones are farther away, and whiter ones are nearer. The simulation showcases Roman’s power to conduct large, deep surveys and study the universe statistically in ways that aren’t possible with current telescopes.

One Roman simulation is helping scientists plan how to study cosmic evolution by teaming up with other telescopes, like the Vera C. Rubin Observatory. It’s based on galaxy and dark matter models combined with real data from other telescopes. It envisions a big patch of the sky Roman will survey when it launches by 2027. Scientists are exploring the simulation to make observation plans so Roman will help us learn as much as possible. It’s a sneak peek at what we could figure out about how and why our universe has changed dramatically across cosmic epochs.

This video begins by showing the most distant galaxies in the simulated deep field image in red. As it zooms out, layers of nearer (yellow and white) galaxies are added to the frame. By studying different cosmic epochs, Roman will be able to trace the universe's expansion history, study how galaxies developed over time, and much more.

As part of the real future survey, Roman will study the structure and evolution of the universe, map dark matter – an invisible substance detectable only by seeing its gravitational effects on visible matter – and discern between the leading theories that attempt to explain why the expansion of the universe is speeding up. It will do it by traveling back in time…well, sort of.

Seeing into the past

Looking way out into space is kind of like using a time machine. That’s because the light emitted by distant galaxies takes longer to reach us than light from ones that are nearby. When we look at farther galaxies, we see the universe as it was when their light was emitted. That can help us see billions of years into the past. Comparing what the universe was like at different ages will help astronomers piece together the way it has transformed over time.

The animation starts with a deep field image of the universe, showing warm toned galaxies as small specks dusted on a black backdrop. Then the center is distorted as additional layers of galaxies are added. The center appears to bulge toward the viewer, and galaxies are enlarged and smeared into arcs. Credit: Caltech-IPAC/R. Hurt

This animation shows the type of science that astronomers will be able to do with future Roman deep field observations. The gravity of intervening galaxy clusters and dark matter can lens the light from farther objects, warping their appearance as shown in the animation. By studying the distorted light, astronomers can study elusive dark matter, which can only be measured indirectly through its gravitational effects on visible matter. As a bonus, this lensing also makes it easier to see the most distant galaxies whose light they magnify.

The simulation demonstrates how Roman will see even farther back in time thanks to natural magnifying glasses in space. Huge clusters of galaxies are so massive that they warp the fabric of space-time, kind of like how a bowling ball creates a well when placed on a trampoline. When light from more distant galaxies passes close to a galaxy cluster, it follows the curved space-time and bends around the cluster. That lenses the light, producing brighter, distorted images of the farther galaxies.

Roman will be sensitive enough to use this phenomenon to see how even small masses, like clumps of dark matter, warp the appearance of distant galaxies. That will help narrow down the candidates for what dark matter could be made of.

Three small squares filled with bluish dots emerge from a black screen. The black background is then filled with bluish dots too, and then the frame zooms out to see a much larger area of the dots. Credit: NASA's Goddard Space Flight Center and A. Yung

In this simulated view of the deep cosmos, each dot represents a galaxy. The three small squares show Hubble's field of view, and each reveals a different region of the synthetic universe. Roman will be able to quickly survey an area as large as the whole zoomed-out image, which will give us a glimpse of the universe’s largest structures.

Constructing the cosmos over billions of years

A separate simulation shows what Roman might expect to see across more than 10 billion years of cosmic history. It’s based on a galaxy formation model that represents our current understanding of how the universe works. That means that Roman can put that model to the test when it delivers real observations, since astronomers can compare what they expected to see with what’s really out there.

A cone shaped assortment of blue dots is on a grid. The tip of the cone is labeled "present day," and the other end is labeled "13.4 billion years ago." Three slices from the middle are pulled out and show the universe's structure developing over time. Credit: NASA's Goddard Space Flight Center and A. Yung

In this side view of the simulated universe, each dot represents a galaxy whose size and brightness corresponds to its mass. Slices from different epochs illustrate how Roman will be able to view the universe across cosmic history. Astronomers will use such observations to piece together how cosmic evolution led to the web-like structure we see today.

This simulation also shows how Roman will help us learn how extremely large structures in the cosmos were constructed over time. For hundreds of millions of years after the universe was born, it was filled with a sea of charged particles that was almost completely uniform. Today, billions of years later, there are galaxies and galaxy clusters glowing in clumps along invisible threads of dark matter that extend hundreds of millions of light-years. Vast “cosmic voids” are found in between all the shining strands.

Astronomers have connected some of the dots between the universe’s early days and today, but it’s been difficult to see the big picture. Roman’s broad view of space will help us quickly see the universe’s web-like structure for the first time. That’s something that would take Hubble or Webb decades to do! Scientists will also use Roman to view different slices of the universe and piece together all the snapshots in time. We’re looking forward to learning how the cosmos grew and developed to its present state and finding clues about its ultimate fate.

Thousands of small, light and deep blue dots cover a black background representing galaxies in a simulated universe. A tiny white square is labeled "Hubble." A set of 18 much larger squares, oriented in three curved rows, are labeled "Roman." Credit: NASA's Goddard Space Flight Center and A. Yung

This image, containing millions of simulated galaxies strewn across space and time, shows the areas Hubble (white) and Roman (yellow) can capture in a single snapshot. It would take Hubble about 85 years to map the entire region shown in the image at the same depth, but Roman could do it in just 63 days. Roman’s larger view and fast survey speeds will unveil the evolving universe in ways that have never been possible before.

Roman will explore the cosmos as no telescope ever has before, combining a panoramic view of the universe with a vantage point in space. Each picture it sends back will let us see areas that are at least a hundred times larger than our Hubble or James Webb space telescopes can see at one time. Astronomers will study them to learn more about how galaxies were constructed, dark matter, and much more.

The simulations are much more than just pretty pictures – they’re important stepping stones that forecast what we can expect to see with Roman. We’ve never had a view like Roman’s before, so having a preview helps make sure we can make the most of this incredible mission when it launches.

Learn more about the exciting science this mission will investigate on Twitter and Facebook.

Make sure to follow us on Tumblr for your regular dose of space!


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2 years ago

5 Years, 8 Discoveries: NASA Exoplanet Explorer Sees Dancing Stars & a Star-Shredding Black Hole

TESS images build in vertical strips of four individual squares. Each square shows a small section of sky. They come together to form a flattened look at Earth’s sky as seen through the TESS telescope. It is an area shown in black-and-white with the bright, dusty Milky way curving through the center of the image. The north and south ecliptic poles lie at the top and bottom of the image. The Andromeda galaxy is the small, bright oval near the upper right edge. The Large Magellanic Cloud can be seen along the bottom edge just left of center. Above and to the left of it shine the Small Magellanic Cloud and the bright star cluster 47 Tucanae. Credit: NASA/MIT/TESS and Ethan Kruse (University of Maryland College Park)

This all-sky mosaic was constructed from 912 Transiting Exoplanet Survey Satellite (TESS) images. Prominent features include the Milky Way, a glowing arc that represents the bright central plane of our galaxy, and the Large and Small Magellanic Clouds – satellite galaxies of our own located, respectively, 160,000 and 200,000 light-years away. In the northern sky, look for the small, oblong shape of the Andromeda galaxy (M 31), the closest big spiral galaxy, located 2.5 million light-years away. The black regions are areas of sky that TESS didn’t image. Credit: NASA/MIT/TESS and Ethan Kruse (University of Maryland College Park)

On April 18, 2018, we launched the Transiting Exoplanet Survey Satellite, better known as TESS. It was designed to search for planets beyond our solar system – exoplanets – and to discover worlds for our James Webb Space Telescope, which launched three years later, to further explore. TESS images sections of sky, one hemisphere at a time. When we put all the images together, we get a great look at Earth’s sky!

In its five years in space, TESS has discovered 326 planets and more than 4,300 planet candidates. Along the way, the spacecraft has observed a plethora of other objects in space, including watching as a black hole devoured a star and seeing six stars dancing in space. Here are some notable results from TESS so far:

An infographic with a blue line drawing of the TESS spacecraft is headlined, “TESS, By the Numbers”. It is followed by large numbers with explanations: 329 exoplanets discovered, 4,300 plus exoplanet candidates; 1,500 research papers; 93 percent of sky observed; 5 years in space; 251 terabytes of image data; 467,768 objects observed at high precision; 50 nations contributing science. Credit: NASA/JPL-Caltech

During its first five years in space, our Transiting Exoplanet Survey Satellite has discovered exoplanets and identified worlds that can be further explored by the James Webb Space Telescope. Credit: NASA/JPL-Caltech

1. TESS’ first discovery was a world called Pi Mensae c. It orbits the star Pi Mensae, about 60 light-years away from Earth and visible to the unaided eye in the Southern Hemisphere. This discovery kicked off NASA's new era of planet hunting.

2. Studying planets often helps us learn about stars too! Data from TESS & Spitzer helped scientists detect a planet around the young, flaring star AU Mic, providing a unique way to study how planets form, evolve, and interact with active stars.

A vintage style travel poster shows giant flares from a giant, bright young star in oranges, reds and bright yellow burst from the star, affecting a nearby planet. You can see the planet’s atmosphere being blasted away by the energy. It says, Located less than 32 light-years from Earth, AU Microscopii is among the youngest planetary systems ever observed by astronomers, and its star throws vicious temper tantrums! You’ve heard of the “terrible twos”? Well, AU Mic is in the midst of its terrible 22 … millions! This devilish young system holds planet AU Mic b captive inside a looming disk of ghostly dust and ceaselessly torments it with deadly blasts of X-rays and other radiation, thwarting any chance of life… as we know it! Beware! There is no escaping the stellar fury of this system. The monstrous flares of AU Mic will have you begging for eternal darkness. Credit: NASA/JPL-Caltech
Ubicado a menos de 32 años luz de la Tierra, AU Microscopii se encuentra entre los sistemas planetarios más jóvenes jamás observados por los astrónomos, ¡y su estrella tiene unas brutales rabietas! ¿Has oído hablar de los "terribles dos años"? Pues AU Mic está en medio de sus terribles 22… ¡millones de años! Este sistema joven diabólico mantiene cautivo a su planeta, AU Mic b, dentro de un disco de polvo fantasmal y lo atormenta incesantemente con explosiones mortales de rayos X y otras radiaciones, frustrando cualquier posibilidad de vida ... ¡tal como la conocemos! ¡Cuidado! No hay escapatoria a la furia estelar de este sistema. Las llamaradas monstruosas de AU Mic te harán rogar por la oscuridad eterna. Crédito de imagen: NASA/JPL-Caltech

Located less than 32 light-years from Earth, AU Microscopii is among the youngest planetary systems ever observed by astronomers, and its star throws vicious temper tantrums. This devilish young system holds planet AU Mic b captive inside a looming disk of ghostly dust and ceaselessly torments it with deadly blasts of X-rays and other radiation, thwarting any chance of life… as we know it! Beware! There is no escaping the stellar fury of this system. The monstrous flares of AU Mic will have you begging for eternal darkness. Credit: NASA/JPL-Caltech

3. In addition to finding exoplanets on its own, TESS serves as a pathfinder for the James Webb Space Telescope. TESS discovered the rocky world LHS 3844 b, but Webb will tell us more about its composition. Our telescopes, much like our scientists, work together.

4. Though TESS may be a planet-hunter, it also helps us study black holes! In 2019, TESS saw a ‘‘tidal disruption event,’’ otherwise known as a black hole shredding a star.

An animated illustration shows a tidal disruption, which occurs when a passing star gets too close to a black hole and is torn apart into a stream of gas. Some of the gas eventually settles into a structure around the black hole called an accretion disk. Credit: NASA's Goddard Space Flight Center

When a star strays too close to a black hole, intense tides break it apart into a stream of gas. The tail of the stream escapes the system, while the rest of it swings back around, surrounding the black hole with a disk of debris. Credit: NASA's Goddard Space Flight Center

5. In 2020, TESS discovered its first Earth-size world in the habitable zone of its star – the distance from a star at which liquid water could exist on a planet’s surface. Earlier this year, a second rocky planet was discovered in the system.

In an animation, four planets are shown orbiting a red dwarf star labeled TOI 700. Planets b and c orbit well within a region overlaid in green and labeled optimistic habitable zone and overlaid in yellow and labeled optimistic habitable zone. Planet d orbits consistently in the conservative habitable zone, while planet e moves between the conservative and optimistic habitable zone. Credit: NASA Goddard Space Flight Center

You can see the exoplanets that orbit the star TOI 700 moving within two marked habitable zones, a conservative habitable zone, and an optimistic habitable zone. Planet d orbits within the conservative habitable zone, while planet e moves within an optimistic habitable zone, the range of distances from a star where liquid surface water could be present at some point in a planet’s history. Credit: NASA Goddard Space Flight Center

6. Astronomers used TESS to find a six-star system where all stars undergo eclipses. Three binary pairs orbit each other, and, in turn, the pairs are engaged in an elaborate gravitational dance in a cosmic ballroom 1,900 light-years away in the constellation Eridanus.

This diagram depicts six stars that interact with each other in complex orbits. The stars are arranged in pairs: Systems A, B, and C, are each shown with one larger white star and one smaller orange star. The two stars of System A, in the upper left, are connected by a red oval and labeled "1.3-day orbit." The two stars of System C, just below System A, are connected by a teal oval and labeled "1.6-day orbit." These two systems orbit each other, shown as a larger blue oval connecting the two and labeled "A and C orbit every 4 years." In the bottom right of the image, the two stars of System B are connected by a green oval and labeled "8.2-day orbit." System B orbits the combined AC system, shown as a very large lilac oval labeled "AC and B orbit every 2,000 years." A caption at the bottom of the image notes, "Star sizes are to scale, orbits are not." The image is watermarked with “Illustration” and “Credit: NASA's Goddard Space Flight Center.” Credit: NASA

7. Thanks to TESS, we learned that Delta Scuti stars pulse to the beat of their own drummer. Most seem to oscillate randomly, but we now know HD 31901 taps out a beat that merges 55 pulsation patterns.

An animation shows a bright blue-white star pulsing with vibrations. In a cutaway that reveals the star’s inner workings, waves are represented by blue arrows and they radiate from the center outward to the star’s surface and back again. 
Credit: NASA’s Goddard Space Flight Center

Sound waves bouncing around inside a star cause it to expand and contract, which results in detectable brightness changes. This animation depicts one type of Delta Scuti pulsation — called a radial mode — that is driven by waves (blue arrows) traveling between the star's core and surface. In reality, a star may pulsate in many different modes, creating complicated patterns that enable scientists to learn about its interior. Credit: NASA’s Goddard Space Flight Center

8. Last is a galaxy that flares like clockwork! With TESS and Swift, astronomers identified the most predictably and frequently flaring active galaxy yet. ASASSN-14ko, which is 570 million light-years away, brightens every 114 days!

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2 years ago

12 Great Gifts from Astronomy

This is a season where our thoughts turn to others and many exchange gifts with friends and family. For astronomers, our universe is the gift that keeps on giving. We’ve learned so much about it, but every question we answer leads to new things we want to know. Stars, galaxies, planets, black holes … there are endless wonders to study.

In honor of this time of year, let’s count our way through some of our favorite gifts from astronomy.

Our first astronomical gift is … one planet Earth

So far, there is only one planet that we’ve found that has everything needed to support life as we know it — Earth. Even though we’ve discovered over 5,200 planets outside our solar system, none are quite like home. But the search continues with the help of missions like our Transiting Exoplanet Survey Satellite (TESS). And even you (yes, you!) can help in the search with citizen science programs like Planet Hunters TESS and Backyard Worlds.

This animated visualization depicts Earth rotating in front of a black background. Land in shades of tan and green lay among vast blue oceans, with white clouds swirling in the atmosphere. The image is watermarked with the text “Credit: NASA/Goddard Space Flight Center Scientific Visualization Studio” and “visualization.”

Our second astronomical gift is … two giant bubbles

Astronomers found out that our Milky Way galaxy is blowing bubbles — two of them! Each bubble is about 25,000 light-years tall and glows in gamma rays. Scientists using data from our Fermi Gamma-ray Space Telescope discovered these structures in 2010, and we're still learning about them.

This image captures the majestic “Fermi bubbles” that extend above and below our Milky Way galaxy, set against the black background of space. A glowing blue line horizontally crosses the center of the image, showing our perspective from Earth of our galaxy’s spiral arms and the wispy clouds of material above and below it. Cloudy bubbles, colored deep magenta to represent Fermi’s gamma-ray vision, extend above and below the galactic plane. These bubbles are enormous, extending roughly half of the Milky Way's diameter and filling much of the top and bottom of the image. The image is watermarked “Credit: NASA/DOE/Fermi LAT Collaboration.”

Our third astronomical gift is … three types of black holes

Most black holes fit into two size categories: stellar-mass goes up to hundreds of Suns, and supermassive starts at hundreds of thousands of Suns. But what happens between those two? Where are the midsize ones? With the help of NASA’s Hubble Space Telescope, scientists found the best evidence yet for that third, in between type that we call intermediate-mass black holes. The masses of these black holes should range from around a hundred to hundreds of thousands of times the Sun’s mass. The hunt continues for these elusive black holes.

This cartoon depicts two black holes as birds, with a small one representing a stellar-mass black hole on the left and an enormous one representing a supermassive black hole on the right. These two birds appear on a tan background and flap their wings, and then a circle with three question marks pops up between them to represent the intermediate-mass black holes that scientists are hunting for. The image is watermarked “Credit: NASA’s Goddard Space Flight Center.”

Our fourth and fifth astronomical gifts are … Stephan’s Quintet

When looking at this stunning image of Stephan’s Quintet from our James Webb Space Telescope, it seems like five galaxies are hanging around one another — but did you know that one of the galaxies is much closer than the others? Four of the five galaxies are hanging out together about 290 million light-years away, but the fifth and leftmost galaxy in the image below — called NGC 7320 — is actually closer to Earth at just 40 million light-years away.

A group of five galaxies that appear close to each other in the sky: two in the middle, one toward the top, one to the upper left, and one toward the bottom. Four of the five appear to be touching. One is somewhat separated. In the image, the galaxies are large relative to the hundreds of much smaller (more distant) galaxies in the background. All five galaxies have bright white cores. Each has a slightly different size, shape, structure, and coloring. Scattered across the image, in front of the galaxies are a number of foreground stars with diffraction spikes: bright white points, each with eight bright lines radiating out from the center. The image is watermarked with the text “Credits: NASA, ESA, CSA, and STScI.”

Our sixth astronomical gift is … an eclipsing six-star system

Astronomers found a six-star system where all of the stars undergo eclipses, using data from our TESS mission, a supercomputer, and automated eclipse-identifying software. The system, called TYC 7037-89-1, is located 1,900 light-years away in the constellation Eridanus and the first of its kind we’ve found.

This diagram shows the sextuple star system TYC 7037-89-1, a group of six stars that interact with each other in complex orbits. The stars are arranged in pairs: System A, System B, and System C, each of which is shown as having one larger white star and one smaller yellow star. The two stars of System A, in the upper left, are connected by a red oval and labeled "1.3-day orbit." The two stars of System C, just below System A, are connected by a turquoise oval and labeled "1.6-day orbit." Additionally, these two systems orbit each other, shown as a larger blue oval connecting the two and labeled "A and C orbit every 4 years." On the other side of the image, in the bottom right, the two stars of System B are connected by a green oval and labeled "8.2-day orbit." Lastly, Systems A, B and C all interact with System B orbiting the combined A-C system, shown as a very large lilac oval labeled "AC and B orbit every 2,000 years." A caption at the bottom of the image notes, "Star sizes are to scale, orbits are not." The image is watermarked with the text “Illustration” and “Credit: NASA's Goddard Space Flight Center.”

Our seventh astronomical gift is … seven Earth-sized planets

In 2017, our now-retired Spitzer Space Telescope helped find seven Earth-size planets around TRAPPIST-1. It remains the largest batch of Earth-size worlds found around a single star and the most rocky planets found in one star’s habitable zone, the range of distances where conditions may be just right to allow the presence of liquid water on a planet’s surface.

Further research has helped us understand the planets’ densities, atmospheres, and more!

his animated image shows an artist's concept of the star TRAPPIST-1, an ultra-cool dwarf, and the seven Earth-size planets orbiting it. TRAPPIST-1 is large and glows bright orange, while the planets are smaller and in shades of cool gray-blue. The image is highly stylized to look like glowing balls sitting on a shiny surface, and neither the sizes nor distances are to scale. The planets closer to TRAPPIST-1 have droplets of water standing on the surface around them, indicating that they may have liquid water. Planets further away have frost around them, indicating that those are more likely to have significant amounts of ice, especially on the side that faces away from the star. Our view pans across the system, from the center outward, and faint tan rings depict the orbits of each planet. The image is watermarked with the text “Illustration” and “Credit: NASA/JPL-Caltech/R. Hurt (IPAC).”

Our eighth astronomical gift is … an (almost) eight-foot mirror

The primary mirror on our Nancy Grace Roman Space Telescope is approximately eight feet in diameter, similar to our Hubble Space Telescope. But Roman can survey large regions of the sky over 1,000 times faster, allowing it to hunt for thousands of exoplanets and measure light from a billion galaxies.

Side profile of a man standing in front of the Nancy Grace Roman Space Telescope Primary mirror. The man wears a long white coat, hair net, facemask, and glasses. The man is standing to the left of the mirror, and looking at it. The mirror faces the man, so it appears to be looking back at him. The mirror is a flat, smooth, silver disk with a black cylinder protruding from its center. Behind the mirror, a black square houses hardware for the mirror. The image is watermarked “Credit: NASA/Chris Gunn.”

Our ninth astronomical gift is … a kilonova nine days later

In 2017, the National Science Foundation (NSF)’s Laser Interferometer Gravitational-Wave Observatory (LIGO) and European Gravitational Observatory’s Virgo detected gravitational waves from a pair of colliding neutron stars. Less than two seconds later, our telescopes detected a burst of gamma rays from the same event. It was the first time light and gravitational waves were seen from the same cosmic source. But then nine days later, astronomers saw X-ray light produced in jets in the collision’s aftermath. This later emission is called a kilonova, and it helped astronomers understand what the slower-moving material is made of.

This animated illustration shows what happened in the nine days following a neutron star merger known as GW170817, detected on Aug. 17, 2017. In the first part of the animation, a pair of glowing blue neutron stars spiral quickly towards each other and merge with a bright flash. The merger creates gravitational waves (shown as pale arcs rippling out from the center), a near-light-speed jet that produced gamma rays (shown as brown cones and a rapidly-traveling magenta glow erupting from the center of the collision), and a donut-shaped ring of expanding blue debris around the center of the explosion. A variety of colors represent the many wavelengths of light produced by the kilonova, creating violet to blue-white to red bursts at the top and bottom of the collision. In the second part of the animation, we see the collision as it would appear from Earth, looking like a burst of red light in the lower left and a huge umbrella-shaped cascade of blue light in the upper right, representing X-rays.  The image is watermarked with the text “Credit: NASA's Goddard Space Flight Center/CI Lab” and “Illustration.”

Our tenth astronomical gift is … NuSTAR’s ten-meter-long mast

Our NuSTAR X-ray observatory is the first space telescope able to focus on high-energy X-rays. Its ten-meter-long (33 foot) mast, which deployed shortly after launch, puts NuSTAR’s detectors at the perfect distance from its reflective optics to focus X-rays. NuSTAR recently celebrated 10 years since its launch in 2012.

This animation shows an artist’s concept of the NuSTAR X-ray observatory orbiting above the blue marble of Earth and deploying its 10-meter-long (33 foot) mast shortly after launch in 2012. NuSTAR is roughly cylindrical, with a shiny silver covering and a pair of blue solar panels on each of its sides. As we pan around the spacecraft, silver scaffolding extends from inside, separating the ends of the telescope to the right distance to begin observing the universe in X-rays. The image is watermarked with the text “Illustration” and “Credit: Credit: NASA/JPL-Caltech.”

Our eleventh astronomical gift is … eleven days of observations

How long did our Hubble Space Telescope stare at a seemingly empty patch of sky to discover it was full of thousands of faint galaxies? More than 11 days of observations came together to capture this amazing image — that’s about 1 million seconds spread over 400 orbits around Earth!

This animated image zooms into the Hubble Ultra Deep Field, showing how a tiny patch of “empty” sky turned out to contain about 10,000 galaxies. The sequence begins with a starry backdrop, then we begin to zoom into the center of this image. As we travel, larger and brighter objects come into view, including dazzling spiral and elliptical galaxies in reds, oranges, blues, and purples. The image is watermarked with the text “Credit: NASA, G. Bacon and Z. Levay (STScI).”

Our twelfth astronomical gift is … a twelve-kilometer radius

Pulsars are collapsed stellar cores that pack the mass of our Sun into a whirling city-sized ball, compressing matter to its limits. Our NICER telescope aboard the International Space Station helped us precisely measure one called J0030 and found it had a radius of about twelve kilometers — roughly the size of Chicago! This discovery has expanded our understanding of pulsars with the most precise and reliable size measurements of any to date.

In this simulation of a pulsar’s magnetic fields, dozens of thin lines dance around a central gray sphere, which is the collapsed core of a dead massive star. Some of these lines, colored orange, form loops on the surface of the sphere. Others, colored blue, arc away from two spots on the lower half of the sphere and vanish into the black background. The image is watermarked with the text “Simulation” and “Credit: NASA's Goddard Space Flight Center.”

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2 years ago

Why Do X-Ray Mirrors Look So Unusual?

Completed quadrant of an X-ray Mirror Assembly, under development for the JAXA/NASA XRISM mission. It is shaped like a fan with thin metal struts holding it together.

Does the object in this image look like a mirror? Maybe not, but that’s exactly what it is! To be more precise, it’s a set of mirrors that will be used on an X-ray telescope. But why does it look nothing like the mirrors you’re familiar with? To answer that, let’s first take a step back. Let’s talk telescopes.

How does a telescope work?

The basic function of a telescope is to gather and focus light to amplify the light’s source. Astronomers have used telescopes for centuries, and there are a few different designs. Today, most telescopes use curved mirrors that magnify and focus light from distant objects onto your eye, a camera, or some other instrument. The mirrors can be made from a variety of materials, including glass or metal.

Diagram showing a reflecting telescope with a pair of mirrors to focus the light on the detector — in this case, an observer’s eye. The diagram shows the “flow” of light, which starts at a distant galaxy, enters the telescope and bounces off the primary mirror at the bottom of the telescope. Then the light moves to the secondary mirror which redirects the light out of the side of the telescope tube into the observer’s eye.

Space telescopes like the James Webb and Hubble Space Telescopes use large mirrors to focus light from some of the most distant objects in the sky. However, the mirrors must be tailored for the type and range of light the telescope is going to capture—and X-rays are especially hard to catch.

X-rays versus mirrors

X-rays tend to zip through most things. This is because X-rays have much smaller wavelengths than most other types of light. In fact, X-rays can be smaller than a single atom of almost every element. When an X-ray encounters some surfaces, it can pass right between the atoms!

X-ray image of a human elbow. Denser materials, like bone, stop more X-rays than skin and muscle.

Doctors use this property of X-rays to take pictures of what’s inside you. They use a beam of X-rays that mostly passes through skin and muscle but is largely blocked by denser materials, like bone. The shadow of what was blocked shows up on the film.

This tendency to pass through things includes most mirrors. If you shoot a beam of X-rays into a standard telescope, most of the light would go right through or be absorbed. The X-rays wouldn’t be focused by the mirror, and we wouldn’t be able to study them.

Animation first showing a plane of balls face-on and an arrow passing through the space between the balls. Then the angle changes to show the balls edge-on and an arrow bouncing off the top.

X-rays can bounce off a specially designed mirror, one turned on its side so that the incoming X-rays arrive almost parallel to the surface and glance off it. At this shallow angle, the space between atoms in the mirror's surface shrinks so much that X-rays can't sneak through. The light bounces off the mirror like a stone skipping on water. This type of mirror is called a grazing incidence mirror.

A metallic onion

Telescope mirrors curve so that all of the incoming light comes to the same place. Mirrors for most telescopes are based on the same 3D shape — a paraboloid. You might remember the parabola from your math classes as the cup-shaped curve. A paraboloid is a 3D version of that, spinning it around the axis, a little like the nose cone of a rocket. This turns out to be a great shape for focusing light at a point.

A line drawing of a parabola - a cup-shaped curve, shown here on its side - spins around to create a 3D shape. The word “paraboloid” shows on the screen. Then part of the curve fades away, leaving behind two things:  a small concave circle, which was one end of the paraboloid, labeled “Radio dishes; optical, infrared and ultraviolet telescope mirrors,” and a cylinder with sloping walls, which was the part of the edges of the paraboloid, labeled “X-ray mirrors.”

Mirrors for visible and infrared light and dishes for radio light use the “cup” portion of that paraboloid. For X-ray astronomy, we cut it a little differently to use the wall. Same shape, different piece. The mirrors for visible, infrared, ultraviolet, and radio telescopes look like a gently-curving cup. The X-ray mirror looks like a cylinder with very slightly angled walls.

The image below shows how different the mirrors look. On the left is one of the Chandra X-ray Observatory’s cylindrical mirrors. On the right you can see the gently curved round primary mirror for the Stratospheric Observatory for Infrared Astronomy telescope.

On the left, a technician stands next to a cylinder-shaped mirror designed for X-ray astronomy. The mirror is held in a frame a little off the ground, and is about as tall as the technician. On the right, two technicians inspect a round mirror for optical astronomy.

If we use just one grazing incidence mirror in an X-ray telescope, there would be a big hole, as shown above (left). We’d miss a lot of X-rays! Instead, our mirror makers fill in that cylinder with layers and layers of mirrors, like an onion. Then we can collect more of the X-rays that enter the telescope, giving us more light to study.

Completed X-ray Mirror Assembly for the X-ray Imaging and Spectroscopy Mission (XRISM, pronounced “crism”), which is a collaboration between the Japan Aerospace Exploration Agency (JAXA) and NASA, along with ESA participation. The assembly has thin metal struts fanning outward from a silver ring in the center of the image. Shiny ridge surfaces (actually many thin mirrors!) fill in the spaces between the struts.

Nested mirrors like this have been used in many X-ray telescopes. Above is a close-up of the mirrors for an upcoming observatory called the X-ray Imaging and Spectroscopy Mission (XRISM, pronounced “crism”), which is a Japan Aerospace Exploration Agency (JAXA)-led international collaboration between JAXA, NASA, and the European Space Agency (ESA).

The XRISM mirror assembly uses thin, gold-coated mirrors to make them super reflective to X-rays. Each of the two assemblies has 1,624 of these layers packed in them. And each layer is so smooth that the roughest spots rise no more than one millionth of a millimeter.

Chandra observations of the Perseus galaxy cluster showing turbulence in the hot X-ray-emitting gas.

Why go to all this trouble to collect this elusive light? X-rays are a great way to study the hottest and most energetic areas of the universe! For example, at the centers of certain galaxies, there are black holes that heat up gas, producing all kinds of light. The X-rays can show us light emitted by material just before it falls in.

Stay tuned to NASA Universe on Twitter and Facebook to keep up with the latest on XRISM and other X-ray observatories.

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3 years ago

Our Weird and Wonderful Galaxy of Black Holes

Black holes are hard to find. Like, really hard to find. They are objects with such strong gravity that light can’t escape them, so we have to rely on clues from their surroundings to find them.

When a star weighing more than 20 times the Sun runs out of fuel, it collapses into a black hole. Scientists estimate that there are tens of millions of these black holes dotted around the Milky Way, but so far we’ve only identified a few dozen. Most of those are found with a star, each circling around the other. Another name for this kind of pair is a binary system.That’s because under the right circumstances material from the star can interact with the black hole, revealing its presence. 

The visualization above shows several of these binary systems found in our Milky Way and its neighboring galaxy. with their relative sizes and orbits to scale. The video even shows each system tilted the way we see it here from our vantage point on Earth. Of course, as our scientists gather more data about these black holes, our understanding of them may change.   

The close orbit of a star and black hole causes the star to lose part of its outer layers to the black hole. A panning shot comes from behind a glowing star and reveals a black hole pulling a stream of stellar material into a swirling, hot disk around it.

If the star and black hole orbit close enough, the black hole can pull material off of its stellar companion! As the material swirls toward the black hole, it forms a flat ring called an accretion disk. The disk gets very hot and can flare, causing bright bursts of light.

In this visualization, an off-white, round star orbits around a black hole with glowing orange material encircling it. The black hole is pulling glowing white material off the star as they orbit each other. V404 Cygni is a black hole that erupted in 1989 and 2015 with an X-ray nova. It lies at a distance of 8,200 light-years. The black hole has a mass of 12 times the Sun, and its companion star has just under two Sun’s worth of mass. They orbit each other every 6.5 days.

V404 Cygni, depicted above, is a binary system where a star slightly smaller than the Sun orbits a black hole 10 times its mass in just 6.5 days. The black hole distorts the shape of the star and pulls material from its surface. In 2015, V404 Cygni came out of a 25-year slumber, erupting in X-rays that were initially detected by our Swift satellite. In fact, V404 Cygni erupts every couple of decades, perhaps driven by a build-up of material in the outer parts of the accretion disk that eventually rush in. 

An illustration depicts what astronomers think is happening within a binary system with a high-mass star and a stellar-mass black hole. A huge, blue-white star radiates strands of 'wind' from its perimeter, with a bright object just to its left. The bright object is the shining disk of material that has collected from the star’s wind and swirls around the black hole before falling in.

In other cases, the black hole’s companion is a giant star with a strong stellar wind. This is like our Sun’s solar wind, but even more powerful. As material rushes out from the companion star, some of it is captured by the black hole’s gravity, forming an accretion disk.

A bright blue star and a black hole with a swirling disk of hot, glowing material orbit each other in this visualization of the Cygnus X-1 system. Cygnus X-1 is the first confirmed black hole. It lies at a distance of 7,200 light-years. The black hole has a mass of 21 times the Sun and its companion star has 40 Sun’s worth of mass. They orbit each other every 5.6 days.

A famous example of a black hole powered by the wind of its companion is Cygnus X-1. In fact, it was the first object to be widely accepted as a black hole! Recent observations estimate that the black hole’s mass could be as much as 20 times that of our Sun. And its stellar companion is no slouch, either. It weighs in at about 40 times the Sun.

Two very different black hole systems are shown together in this visualization. In one, called GRS 1915, a bright star and a black hole with a large swirling disk of glowing material orbit each other, filling nearly the whole image. They only complete a small portion of their orbit in the few seconds the GIF plays. The second system is much smaller one called H1705. It has a small, bead-sized star orbiting a tiny black hole that has a small disk of material. The small system completes three orbits in the few seconds the GIF plays.

We know our galaxy is peppered with black holes of many sizes with an array of stellar partners, but we've only found a small fraction of them so far. Scientists will keep studying the skies to add to our black hole menagerie.

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3 years ago

We’re Upgrading Our X-ray Vision!

We’re Upgrading Our X-ray Vision!

Think X-ray vision is a superpower found only in comics and movies? Unlike Superman and Supergirl, NASA has it for real, thanks to the X-ray observatories we’ve sent into orbit.

Now the Imaging X-ray Polarimetry Explorer – IXPE for short – has shot into space to enhance our superpower!

Meet IXPE

We’re Upgrading Our X-ray Vision!

When dentists take X-ray pictures of a tooth, they use a machine that makes X-rays and captures them on a device placed on the opposite side. But X-rays also occur naturally. In astronomy, we observe X-rays made by distant objects to learn more about them.

IXPE will improve astronomers’ knowledge about some of these objects, like black holes, neutron stars, and the expanding clouds made by supernova explosions.

That’s because it will capture a piece of information about X-ray light that has only rarely been measured from space!

We’re Upgrading Our X-ray Vision!

X-ray astronomers have learned a lot about the cosmos by measuring three properties of light – when it arrives, where it’s coming from, and what energies it has (think: colors). Picture these characteristics as making up three of the four sides of a pyramid. The missing piece is a property called polarization.

Polarization tells us how organized light is. This gives astronomers additional clues about how the X-rays were made and what matter they’ve passed through on their way to us. IXPE will explore this previously hidden side of cosmic X-ray sources.

What is polarization?

We’re Upgrading Our X-ray Vision!

All light, from microwaves to gamma rays, is made from pairs of waves traveling together – one carrying electricity and the other magnetism. These two waves always vibrate at right angles (90°) to each other, with their peaks and valleys in sync, and they also vibrate at right angles to their direction of motion.

To keep things simple, we’ll illustrate only one of these waves – the one carrying electricity. If we could zoom into a typical beam of light, we’d see something like the animation above. It’s a mess, with all the wave peaks pointing in random directions.

We’re Upgrading Our X-ray Vision!

When light interacts with matter, it can become better organized. Its electric field can vibrate in a way that keeps all the wave crests pointing in the same direction, as shown above. This is polarized light.

The amount and type of polarization we detect in light tell us more about its origin, as well as any matter it interacted with before reaching us.

Let’s look at the kinds of objects IXPE will study and what it may tell us about them.

Exploring star wrecks

We’re Upgrading Our X-ray Vision!

Exploded stars create vast, rapidly expanding clouds called supernova remnants – like the Jellyfish Nebula above. It formed 4,000 years ago, but even today, the remnant’s heart can tell us about the extreme conditions following the star’s explosion.

X-rays give us a glimpse of the powerful processes at work during and after these explosions. IXPE will map remnants like this, revealing how X-rays are polarized across the entire object. This will help us better understand how these celestial cataclysms take place and evolve.

Magnifying supermagnets

We’re Upgrading Our X-ray Vision!

Some supernovae leave behind neutron stars. They form when the core of a massive star collapses, squeezing more than our Sun’s mass into a ball only as wide as a city.

The collapse greatly ramps up their spin. Some neutron stars rotate hundreds of times a second! Their magnetic fields also get a tremendous boost, becoming trillions of times stronger than Earth’s. One type, called a magnetar, boasts the strongest magnetic fields known – a thousand times stronger than typical neutron stars.

These superdense, superspinning supermagnets frequently erupt in powerful outbursts (illustrated above) that emit lots of X-rays. IXPE will tell astronomers more about these eruptions and the extreme magnetic fields that help drive them.

Closing in on black holes

We’re Upgrading Our X-ray Vision!

Black holes can form when massive stars collapse or when neutron stars crash together. Matter falling toward a black hole quickly settles into a hot, flat structure called an accretion disk. The disk’s inner edge gradually drains into the black hole. Notice how odd the disk appears from certain angles? This happens because the black hole’s extreme gravity distorts the path of light coming from the disk’s far side.

X-rays near the black hole can bounce off the disk before heading to our telescopes, and this polarizes the light. What’s exciting is that the light is polarized differently across the disk. The differences depend both on the energies of the X-rays and on what parts of the disk they strike. IXPE observations will provide astronomers with a detailed picture of what’s happening around black holes in our galaxy that can’t be captured in any other way.

By tracking how X-ray light is organized, IXPE will add a previously unseen dimension to our X-ray vision. It’s a major upgrade that will give astronomers a whole new perspective on some of the most intriguing objects in the universe.

Keep up with what’s happening in the universe and how we study it by following NASA Universe on Twitter and Facebook.

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4 years ago

Bend Your Mind With Special Relativity

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Ever dreamed of traveling nearly as fast as light? Zipping across the universe to check out the sights seems like it could be fun. But, not so fast. There are a few things you should know before you jump into your rocket. At near the speed of light, the day-to-day physics we know on Earth need a few modifications. And if you’re thinking Albert Einstein will be entering this equation, you’re right!

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We live our daily lives using what scientists call Newtonian physics, as in Isaac Newton, the guy who had the proverbial apple fall on his head. Imagine that you are on a sidewalk, watching your friend walk toward the front of a bus as it drives away. The bus is moving at 30 mph. Your friend walks at 3 mph. To you, your friend is moving at 33 mph — you simply add the two speeds together. (The 30 mph the bus is moving plus 3 mph that your friend is moving inside the bus.) This is a simple example of Newtonian physics.

However, imagine that your friend on the bus turns on a flashlight, and you both measure the speed of its light. You would both measure it to be moving at 670 million mph (or 1 billion kilometers per hour) — this is the speed of light. Even though the flashlight is with your friend on the moving bus, you still both measure the speed of light to be exactly the same. Suddenly you see how Einstein’s physics is different from Newton’s.

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This prediction was a key part of Einstein’s special theory of relativity: The speed of light is the same for any observer, no matter their relative speed. This leads to many seemingly weird effects.  

Before talking about those surprising effects, it’s good to take a moment to talk about point of view. For the rest of this discussion, we’ll assume that you’re at rest — sitting in one spot in space, not moving. And your friend is on a rocket ship that you measure to be traveling at 90% the speed of light. Neither of you is changing speed or direction. Scientists give this a fancy name — an “inertial frame of reference.”

With the stage set, now we can talk about a couple of super-weird effects of traveling near the speed of light. Relativity messes with simple things like distance and time, doing stuff that might blow your mind!

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Let’s say you have a stick that is 36 inches long (91 centimeters). Your friend on the rocket doesn’t know the stick’s length, so they measure it by comparing it to a ruler they have as they zoom past you. They find your stick is just 16 inches (40 centimeters) long — less than half the length you measured! This effect is called length contraction. And if they were moving even faster, your friend would measure your stick to be even shorter. The cool thing about relativity is that both of those measurements are right! We see these effects in particle physics with fast-moving particles.

If your friend was traveling to our nearest neighbor star, Proxima Centauri, how far would they think it was? From Earth, we measure Proxima Centauri to be 4.2 light-years away (where one light-year is the distance light travels in a year, or about 5.8 trillion miles). However, your friend, who is traveling at 90% the speed of light in the rocket, would measure the distance between Earth and Proxima Centauri to be just over 1.8 light-years.

That’s just length … let’s talk about time!

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Now let’s say you and your friend on the rocket have identical synchronized clocks. When your friend reaches Proxima Centauri, they send you a signal, telling you how long their trip took them. Their clock says the trip took just over two years. Remember, they measure the distance to be 1.8 light-years. However, you would see that your clock, which stayed at rest with you, says the trip took 4.7 years — more than twice as long!

This effect is called time dilation — time on moving clocks appears to tick slower.

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None of this accounts for your friend accelerating their rocket or stopping at Proxima Centauri. All of this math gets more complicated if you and your friend were speeding up, slowing down, or changing directions. For instance, if your friend slowed down to stop at Proxima Centauri, they would have aged less than you on their trip!

Now you’re ready for a few tips on near-light-speed travel! Watch the video below for more.

Now, if you need to relax a bit after this whirlwind, near-light-speed trip, you can grab our coloring pages of scenes from the video. And if you enjoyed the trip, download a postcard to send to a friend. Finally, if you want to explore more of the wonders of the universe, follow NASA Universe on Facebook and Twitter.

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5 years ago

Three Ways to Travel at (Nearly) the Speed of Light

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One hundred years ago, Einstein’s theory of general relativity was supported by the results of a solar eclipse experiment. Even before that, Einstein had developed the theory of special relativity — a way of understanding how light travels through space.

Particles of light — photons — travel through a vacuum at a constant pace of more than 670 million miles per hour.

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All across space, from black holes to our near-Earth environment, particles are being accelerated to incredible speeds — some even reaching 99.9% the speed of light! By studying these super fast particles, we can learn more about our galactic neighborhood. 

Here are three ways particles can accelerate:

1) Electromagnetic Fields!

Electromagnetic fields are the same forces that keep magnets on your fridge! The two components — electric and magnetic fields — work together to whisk particles at super fast speeds throughout the universe. In the right conditions, electromagnetic fields can accelerate particles at near-light-speed.

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We can harness electric fields to accelerate particles to similar speeds on Earth! Particle accelerators, like the Large Hadron Collider and Fermilab, use pulsed electromagnetic fields to smash together particles and produce collisions with immense amounts of energy. These experiments help scientists understand the Big Bang and how it shaped the universe!

2) Magnetic Explosions!

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Magnetic fields are everywhere in space, encircling Earth and spanning the solar system. When these magnetic fields run into each other, they can become tangled. When the tension between the crossed lines becomes too great, the lines explosively snap and realign in a process known as magnetic reconnection. Scientists suspect this is one way that particles — for example, the solar wind, which is the constant stream of charged particles from the Sun — are sped up to super fast speeds.

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When magnetic reconnection occurs on the side of Earth facing away from the Sun, the particles can be hurled into Earth’s upper atmosphere where they spark the auroras.

3) Wave-Particle Interactions!

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Particles can be accelerated by interactions with electromagnetic waves, called wave-particle interactions. When electromagnetic waves collide, their fields can become compressed. Charged particles bounce back and forth between the waves, like a ball bouncing between two merging walls. These types of interactions are constantly occurring in near-Earth space and are responsible for damaging electronics on spacecraft and satellites in space.

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Wave-particle interactions might also be responsible for accelerating some cosmic rays from outside our solar system. After a supernova explosion, a hot, dense shell of compressed gas called a blast wave is ejected away from the stellar core. Wave-particle interactions in these bubbles can launch high-energy cosmic rays at 99.6% the speed of light.

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6 years ago

One Year of Leadership

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It’s been one year since Jim Bridenstine was sworn in as our 13th administrator, starting the job on April 23, 2018. Since then, he has led the agency towards taking our nation farther than ever before — from assigning the first astronauts to fly on commercial vehicles to the International Space Station, to witnessing New Horizon’s arrival at the farthest object ever explored, to working to meet the challenge of landing humans on the lunar surface by 2024.

Here is a look at what happened in the last year under the Administrator’s leadership:

1. Assigned the first astronauts to fly on commercial spacecraft to the International Space Station.

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Administrator Bridenstine introduced to the world on Aug. 3, 2018 the first U.S. astronauts who will fly on American-made, commercial spacecraft to and from the International Space Station — an endeavor that will return astronaut launches to U.S. soil for the first time since the space shuttle’s retirement in 2011.

“Today, our country’s dreams of greater achievements in space are within our grasp,” said Administrator Bridenstine. “This accomplished group of American astronauts, flying on new spacecraft developed by our commercial partners Boeing and SpaceX, will launch a new era of human spaceflight.”

2. Announced the first commercial effort to regularly send science payloads to the Moon.

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Administrator Bridenstine announced new Moon partnerships with American companies — an important step to achieving long-term scientific study and human exploration of the Moon and Mars. Nine U.S. companies were named as eligible to bid on NASA delivery services to the Moon through Commercial Lunar Payload Services (CLPS) contracts on Nov. 29, 2018.  

3. Witnessed the teamwork that led to the latest mission to the Red Planet with Mars InSight’s landing.

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On Nov. 26, 2018, the InSight lander successfully touched down on Mars after an almost seven-month, 300-million-mile (485-million-kilometer) journey from Earth. Administrator Bridenstine celebrated with the members of Mars Cube One and Mars InSight team members after the Mars lander successfully landed and began its mission to study the “inner space” of Mars: its crust, mantle and core.

"Today, we successfully landed on Mars for the eighth time in human history,” said NASA Administrator Jim Bridenstine. “InSight will study the interior of Mars, and will teach us valuable science as we prepare to send astronauts to the Moon and later to Mars…The best of NASA is yet to come, and it is coming soon.”

4. Oversaw the arrival of the first American mission to an asteroid designed to return samples and New Horizon’s arrival at Ultima Thule, the farthest object ever explored.

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The spacecraft OSIRIS-REx traveled 1.4 million miles (2.2 million kilometers) to arrive at the asteroid Bennu on Dec. 3. The first asteroid sample mission is helping scientists investigate how planets formed and how life began, as well as improve our understanding of asteroids that could impact Earth. OSIRIS-Rex has already revealed water locked inside the clays that make up the asteroid.

And on the early hours of New Year’s Day, 2019, our New Horizons spacecraft flew past Ultima Thule in Kuiper belt, a region of primordial objects that hold keys to understanding the origins of the solar system.

“In addition to being the first to explore Pluto, today New Horizons flew by the most distant object ever visited by a spacecraft and became the first to directly explore an object that holds remnants from the birth of our solar system,” said Administrator Bridenstine. “This is what leadership in space is all about.”

5. Directed the first major milestone in commercial crew flights with the successful Space X Demo-1 mission.

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Demonstration Mission-1 (Demo-1) was an uncrewed flight test designed to demonstrate a new commercial capability developed under NASA’s Commercial Crew Program. The mission began March 2, when the Crew Dragon launched from NASA’s Kennedy Space Center in Florida and docked to the International Space Station for five days.

“Today’s successful re-entry and recovery of the Crew Dragon capsule after its first mission to the International Space Station marked another important milestone in the future of human spaceflight,” said Administrator Bridenstine. “I want to once again congratulate the NASA and SpaceX teams on an incredible week. Our Commercial Crew Program is one step closer to launching American astronauts on American rockets from American soil.”

6. Is currently working to meet the challenge of advancing human exploration of the lunar surface to 2024.

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Administrator Bridenstine has accomplished a lot since he swore in one year ago — but the best is yet to come. On March 26, Vice President Mike Pence tasked our agency with returning American astronauts to the Moon by 2024 at the fifth meeting of the National Space Council. 

“It is the right time for this challenge, and I assured the Vice President that we, the people of NASA, are up to the challenge,” said Administrator Bridenstine. “There’s a lot of excitement about our plans and also a lot of hard work and challenges ahead, but I know the NASA workforce and our partners are up to it.”

Learn more about what’s still to come this year at NASA:

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6 years ago

Demo-1: What’s the Deal?

Whether or not you caught the SpaceX Crew Dragon launch this past weekend, here’s your chance to learn why this mission, known as Demo-1, is such a big deal.

The First of its Kind

Demo-1 is the first flight test of an American spacecraft designed for humans built and operated by a commercial company. 

Liftoff

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The SpaceX Crew Dragon lifted off at 2:49 a.m. EST Saturday, March 2, on the company’s Falcon 9 rocket from Kennedy Space Center. 

This was the first time in history a commercially-built American crew spacecraft and rocket launched from American soil. 

A New Era in Human Spaceflight

Demo-1: What’s The Deal?

Upon seeing the arriving spacecraft, NASA astronaut Anne McClain snapped a photo from the International Space Station: “Welcome to a new era in human spaceflight.” 

Docking the Dragon

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After making 18 orbits of Earth, the Crew Dragon spacecraft successfully attached to the International Space Station’s Harmony module at 5:51 a.m. EST Sunday, March 3. The Crew Dragon used the station’s new international docking adapter for the first time since astronauts installed it in August 2016. 

The docking phase, in addition to the return and recovery of Crew Dragon, are critical to understanding the system’s ability to support crew flights.

Opening the Hatch

Demo-1: What’s The Deal?

After opening the hatch between the two spacecraft, the crewmates configured Crew Dragon for its stay. 

They installed a ventilation system that cycles air from Crew Dragon to the station, installed window covers and checked valves. After that, the crew was all set for a welcoming ceremony for the visiting vehicle. 

Ripley and Little Earth

Demo-1: What’s The Deal?

Although the test is uncrewed, that doesn’t mean the Crew Dragon is empty. Along for the ride was Ripley, a lifelike test device outfitted with sensors to provide data about potential effects on future astronauts. (There is also a plush Earth doll included inside that can float in the microgravity!)

Inside the Dragon

For future operational missions, Crew Dragon will be able to launch as many as four crew members and carry more than 220 pounds of cargo. This will increase the number of astronauts who are able to live onboard the station, which will create more time for research in the unique microgravity environment.

Integration

Demo-1: What’s The Deal?

Since the arrival of SpaceX Crew Dragon, the three Expedition 58 crew members have returned to normal operations (with some new additions to the team!) 

Undocking

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The Crew Dragon is designed to stay docked to station for up to 210 days, although the spacecraft used for this flight test will remain docked to the space station for only five days, departing Friday, March 8. (We will be providing live coverage — don’t miss it!)

SpaceX and NASA

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Elon Musk, CEO and lead designer at SpaceX, expressed appreciation for NASA’s support: “SpaceX would not be here without NASA, without the incredible work that was done before SpaceX even started and without the support after SpaceX did start.”

Preparation for Demo-2

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NASA and SpaceX will use data from Demo-1 to further prepare for Demo-2, the crewed flight test that will carry NASA astronauts and Doug Hurley and Bob Behnken to the International Space Station. NASA will validate the performance of SpaceX’s systems before putting crew on board for the Demo-2 flight, currently targeted for July 2019.

Demo-1: So What?

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Demo-1 is a big deal because it demonstrates NASA and commercial companies working together to advance future space exploration! With Demo-1’s success, NASA and SpaceX will begin to prepare to safely fly astronauts to the orbital laboratory.

Follow along with mission updates with the Space Station blog.

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6 years ago

Greatest Hits — Craters We Love

Our solar system was built on impacts — some big, some small — some fast, some slow. This week, in honor of a possible newly-discovered large crater here on Earth, here’s a quick run through of some of the more intriguing impacts across our solar system.

1. Mercury: A Basin Bigger Than Texas

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Mercury does not have a thick atmosphere to protect it from space debris. The small planet is riddled with craters, but none as spectacular as the Caloris Basin. “Basin” is what geologists call craters larger than about 186 miles (300 kilometers) in diameter. Caloris is about 950 miles (1,525 kilometers) across and is ringed by mile-high mountains.

For scale, the state of Texas is 773 miles (1,244 kilometers) wide from east to west.

2. Venus: Tough on Space Rocks

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Venus’ ultra-thick atmosphere finishes off most meteors before they reach the surface. The planet’s volcanic history has erased many of its craters, but like almost any place with solid ground in our solar system, there are still impact scars to be found. Most of what we know of Venus’ craters comes from radar images provided by orbiting spacecraft, such as NASA’s Magellan.

Mead Crater is the largest known impact site on Venus. It is about 170 miles (275 kilometers) in diameter. The relatively-flat, brighter inner floor of the crater indicates it was filled with impact melt and/or lava.

3. Earth: Still Craters After All These Years

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Evidence of really big impacts — such as Arizona’s Meteor Crater — are harder to find on Earth. The impact history of our home world has largely been erased by weather and water or buried under lava, rock or ice. Nonetheless, we still find new giant craters occasionally.

A NASA glaciologist has discovered a possible impact crater buried under more than a mile of ice in northwest Greenland.

This follows the finding, announced in November 2018, of a 19-mile (31-kilometer) wide crater beneath Hiawatha Glacier – the first meteorite impact crater ever discovered under Earth’s ice sheets. 

If the second crater, which has a width of over 22 miles (35 kilometers), is ultimately confirmed as the result of a meteorite impact, it will be the 22nd largest impact crater found on Earth.

4. Moon: Our Cratered Companion

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Want to imagine what Earth might look like without its protective atmosphere, weather, water and other crater-erasing features? Look up at the Moon. The Moon’s pockmarked face offers what may be humanity’s most familiar view of impact craters.

One of the easiest to spot is Tycho, the tight circle and bright, radiating splat are easy slightly off center on the lower-left side of the full moon. Closer views of the 53-mile (85 kilometer)-wide crater from orbiting spacecraft reveal a beautiful central peak, topped with an intriguing boulder that would fill about half of a typical city block.

5. Mars: Still Taking Hits

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Mars has just enough atmosphere to ensure nail-biting spacecraft landings, but not enough to prevent regular hits from falling space rocks. This dark splat on the Martian south pole is less than a year old, having formed between July and September 2018. The two-toned blast pattern tells a geologic story. The larger, lighter-colored blast pattern could be the result of scouring by winds from the impact shockwave on ice. The darker-colored inner blast pattern is because the impactor penetrated the thin ice layer, blasting the dark sand underneath in all directions.

6. Ceres: What Lies Beneath

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The bright spots in Ceres’ Occator crater intrigued the world from the moment the approaching Dawn spacecraft first photographed it in 2015. Closer inspection from orbit revealed the spots to be the most visible example of hundreds of bright, salty deposits that decorate the dwarf planet like a smattering of diamonds. The science behind these bright spots is even more compelling: they are mainly sodium carbonate and ammonium chloride that somehow made their way to the surface in a slushy brine from within or below the crust. Thanks to Dawn, scientists have a better sense of how these reflective areas formed and changed over time — processes indicative of an active, evolving world.

7. Comet Tempel 1: We Did It!

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Scientists have long known we can learn a lot from impact craters — so, in 2005, they made one themselves and watched it happen.

On July 4, 2005, NASA’s Deep Impact spacecraft trained its instruments on an 816-pound (370-kilogram) copper impactor as it smashed into comet Tempel 1.

One of the more surprising findings: The comet has a loose, “fluffy” structure, held together by gravity and contains a surprising amount of organic compounds that are part of the basic building blocks of life.

8. Mimas: May the 4th Be With You

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Few Star Wars fans — us included — can resist Obi Wan Kenobi's memorable line “That’s no moon…” when images of Saturn’s moon Mimas pop up on a screen. Despite its Death Star-like appearance, Mimas is most definitely a moon. Our Cassini spacecraft checked, a lot — and the superlaser-looking depression is simply an 81-mile (130-kilometer) wide crater named for the moon’s discoverer, William Herschel.

9. Europa: Say What?

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The Welsh name of this crater on Jupiter’s ocean moon Europa looks like a tongue-twister, but it is easiest pronounced as “pool.” Pwyll is thought to be one of the youngest features we know of on Europa. The bright splat from the impact extends more than 600 miles (about 1,000 kilometers) around the crater, a fresh blanket over rugged, older terrain. “Fresh,” or young, is a relative term in geology; the crater and its rays are likely millions of years old.

10. Show Us Your Greatest Hits

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Got a passion for Stickney, the dominant bowl-shaped crater on one end of Mars’ moon Phobos? Or a fondness for the sponge-like abundance of impacts on Saturn’s battered moon Hyperion (pictured)? There are countless craters to choose from. Share your favorites with us on Twitter, Instagram and Facebook.

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6 years ago

Things That Go Bump in the Gamma Rays

Some people watch scary movies because they like being startled. A bad guy jumps out from around a corner! A monster emerges from the shadows! Scientists experience surprises all the time, but they’re usually more excited than scared. Sometimes theories foreshadow new findings — like when there’s a dramatic swell in the movie soundtrack — but often, discoveries are truly unexpected. 

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Scientists working with the Fermi Gamma-Ray Space Telescope have been jumping to study mysterious bumps in the gamma rays for a decade now. Gamma rays are the highest-energy form of light. Invisible to human eyes, they’re created by some of the most powerful and unusual events and objects in the universe. In celebration of Halloween, here are a few creepy gamma-ray findings from Fermi’s catalog.

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Stellar Graveyards

If you were to walk through a cemetery at night, you’d expect to trip over headstones or grave markers. Maybe you’d worry about running into a ghost. If you could explore the stellar gravesite created when a star explodes as a supernova, you’d find a cloud of debris expanding into interstellar space. Some of the chemical elements in that debris, like gold and platinum, go on to create new stars and planets! Fermi found that supernova remnants IC 443 and W44 also accelerate mysterious cosmic rays, high-energy particles moving at nearly the speed of light. As the shockwave of the supernova expands, particles escape its magnetic field and interact with non-cosmic-ray particles to produce gamma rays. 

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Ghost Particles

But the sources of cosmic rays aren’t the only particle mysteries Fermi studies. Just this July, Fermi teamed up with the IceCube Neutrino Observatory in Antarctica to discover the first source of neutrinos outside our galactic neighborhood. Neutrinos are particles that weigh almost nothing and rarely interact with anything. Around a trillion of them pass through you every second, ghost-like, without you noticing and then continue on their way. (But don’t worry, like a friendly ghost, they don’t harm you!) Fermi traced the neutrino IceCube detected back to a supermassive black hole in a distant galaxy. By the time it reached Earth, it had traveled for 3.7 billion years at almost the speed of light!

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Black Widow Pulsars

Black widows and redbacks are species of spiders with a reputation for devouring their partners. Astronomers have discovered two types of star systems that behave in a similar way. Sometimes when a star explodes as a supernova, it collapses back into a rapidly spinning, incredibly dense star called a pulsar. If there’s a lighter star nearby, it can get stuck in a close orbit with the pulsar, which blasts it with gamma rays, magnetic fields and intense winds of energetic particles. All these combine to blow clouds of material off the low-mass star. Eventually, the pulsar can eat away at its companion entirely.

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Dark Matter

What’s scarier than a good unsolved mystery? Dark matter is a little-understood substance that makes up most of the matter in the universe. The stuff that we can see — stars, people, haunted houses, candy — is made up of normal matter. But our surveys of the cosmos tell us there’s not enough normal matter to keep things working the way they do. There must be another type of matter out there holding everything together. One of Fermi’s jobs is to help scientists narrow down the search for dark matter. Last year, researchers noticed that most of the gamma rays coming from the Andromeda galaxy are confined to its center instead of being spread throughout. One possible explanation is that accumulated dark matter at the center of the galaxy is emitting gamma rays!

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Fermi has helped us learn a lot about the gamma-ray universe over the last 10 years. Learn more about its accomplishments and the other mysteries it’s working to solve. What other surprises are waiting out among the stars?

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6 years ago

A Mesmerizing Model of Monster Black Holes

Just about every galaxy the size of our Milky Way (or bigger) has a supermassive black hole at its center. These objects are ginormous — hundreds of thousands to billions of times the mass of the Sun! Now, we know galaxies merge from time to time, so it follows that some of their black holes should combine too. But we haven’t seen a collision like that yet, and we don’t know exactly what it would look like. 

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A new simulation created on the Blue Waters supercomputer — which can do 13 quadrillion calculations per second, 3 million times faster than the average laptop — is helping scientists understand what kind of light would be produced by the gas around these systems as they spiral toward a merger.

The new simulation shows most of the light produced around these two black holes is UV or X-ray light. We can’t see those wavelengths with our own eyes, but many telescopes can. Models like this could tell the scientists what to look for. 

You may have spotted the blank circular region between the two black holes. No, that’s not a third black hole. It’s a spot that wasn’t modeled in this version of the simulation. Future models will include the glowing gas passing between the black holes in that region, but the researchers need more processing power. The current version already required 46 days!

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The supermassive black holes have some pretty nifty effects on the light created by the gas in the system. If you view the simulation from the side, you can see that their gravity bends light like a lens. When the black holes are lined up, you even get a double lens!

But what would the view be like from between two black holes? In the 360-degree video above, the system’s gas has been removed and the Gaia star catalog has been added to the background. If you watch the video in the YouTube app on your phone, you can moved the screen around to explore this extreme vista. Learn more about the new simulation here. 

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7 years ago

The Universe's Brightest Lights Have Some Dark Origins

Did you know some of the brightest sources of light in the sky come from black holes in the centers of galaxies? It sounds a little contradictory, but it's true! They may not look bright to our eyes, but satellites have spotted oodles of them across the universe. 

One of those satellites is our Fermi Gamma-ray Space Telescope. Fermi has found thousands of these kinds of galaxies in the 10 years it's been operating, and there are many more out there!

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Black holes are regions of space that have so much gravity that nothing - not light, not particles, nada - can escape. Most galaxies have supermassive black holes at their centers - these are black holes that are hundreds of thousands to billions of times the mass of our sun - but active galactic nuclei (also called "AGN" for short, or just "active galaxies") are surrounded by gas and dust that's constantly falling into the black hole. As the gas and dust fall, they start to spin and form a disk. Because of the friction and other forces at work, the spinning disk starts to heat up.

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The disk's heat gets emitted as light - but not just wavelengths of it that we can see with our eyes. We see light from AGN across the entire electromagnetic spectrum, from the more familiar radio and optical waves through to the more exotic X-rays and gamma rays, which we need special telescopes to spot.

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About one in 10 AGN beam out jets of energetic particles, which are traveling almost as fast as light. Scientists are studying these jets to try to understand how black holes - which pull everything in with their huge amounts of gravity - somehow provide the energy needed to propel the particles in these jets.

The Universe's Brightest Lights Have Some Dark Origins

Many of the ways we tell one type of AGN from another depend on how they're oriented from our point of view. With radio galaxies, for example, we see the jets from the side as they're beaming vast amounts of energy into space. Then there's blazars, which are a type of AGN that have a jet that is pointed almost directly at Earth, which makes the AGN particularly bright.  

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Our Fermi Gamma-ray Space Telescope has been searching the sky for gamma ray sources for 10 years. More than half (57%) of the sources it has found have been blazars. Gamma rays are useful because they can tell us a lot about how particles accelerate and how they interact with their environment.

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So why do we care about AGN? We know that some AGN formed early in the history of the universe. With their enormous power, they almost certainly affected how the universe changed over time. By discovering how AGN work, we can understand better how the universe came to be the way it is now.

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Fermi's helped us learn a lot about the gamma-ray universe over the last 10 years. Learn more about Fermi and how we're celebrating its accomplishments all year.

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7 years ago

Black Hole Sculpts an Hourglass Galaxy

When it comes to galaxies, our home, the Milky Way, is rather neat and orderly. Other galaxies can be much more chaotic. For example, the Markarian 573 galaxy has a black hole at its center which is spewing beams of light in opposite directions, giving its inner regions more of an hourglass shape. 

Black Hole Sculpts An Hourglass Galaxy

Our scientists have long been fascinated by this unusual structure, seen above in optical light from the Hubble Space Telescope. Now their search has taken them deeper than ever — all the way into the super-sized black hole at the center of one galaxy.

So, what do we think is going on? When the black hole gobbles up matter, it releases a form of high-energy light called radiation (particularly in the form of X-rays), causing abnormal patterns in the flow of gas. 

Let’s take a closer look.

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Meet Markarian 573, the galaxy at the center of this image from the Sloan Digital Sky Survey, located about 240 million light-years away from Earth in the constellation Cetus. It’s the galaxy’s odd structure and the unusual motions of its components that inspire our scientists to study it.

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As is the case with other so-called active galaxies, the ginormous black hole at the center of Markarian 573 likes to eat stuff. A thick ring of dust and gas accumulates around it, forming a doughnut. This ring only permits light to escape the black hole in two cone-shaped regions within the flat plane of the galaxy — and that’s what creates the hourglass, as shown in the illustration above.

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Zooming out, we can see the two cones of emission (shown in gold in the animation above) spill into the galaxy's spiral arms (blue). As the galaxy rotates, gas clouds in the arms sweep through this radiation, which makes them light up so our scientists can track their movements from Earth.

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What happens next depends on how close the gas is to the black hole. Gas that’s about 2,500 light-years from the black hole picks up speed and streams outward (shown as darker red and blue arrows). Gas that’s farther from the black hole also becomes ionized, but is not driven away and continues its motion around the galaxy as before.

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Here is an actual snapshot of the inner region of Markarian 573, combining X-ray data (blue) from our Chandra X-ray Observatory and radio observations (purple) from the Karl G. Jansky Very Large Array in New Mexico with a visible light image (gold) from our Hubble Space Telescope. Given its strange appearance, we’re left to wonder: what other funky shapes might far-off galaxies take?

For more information about the bizarre structure of Markarian 573, visit http://svs.gsfc.nasa.gov/12657  

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7 years ago

Webb 101: 10 Facts about the James Webb Space Telescope

Did you know…?

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1. Our upcoming James Webb Space Telescope will act like a powerful time machine – because it will capture light that’s been traveling across space for as long as 13.5 billion years, when the first stars and galaxies were formed out of the darkness of the early universe.

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2. Webb will be able to see infrared light. This is light that is just outside the visible spectrum, and just outside of what we can see with our human eyes.

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3. Webb’s unprecedented sensitivity to infrared light will help astronomers to compare the faintest, earliest galaxies to today's grand spirals and ellipticals, helping us to understand how galaxies assemble over billions of years.

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Hubble’s infrared look at the Horsehead Nebula. Credit: NASA/ESA/Hubble Heritage Team

4. Webb will be able to see right through and into massive clouds of dust that are opaque to visible-light observatories like the Hubble Space Telescope. Inside those clouds are where stars and planetary systems are born.

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5. In addition to seeing things inside our own solar system, Webb will tell us more about the atmospheres of planets orbiting other stars, and perhaps even find the building blocks of life elsewhere in the universe.

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Credit: Northrop Grumman

6. Webb will orbit the Sun a million miles away from Earth, at the place called the second Lagrange point. (L2 is four times further away than the moon!)

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7. To preserve Webb’s heat sensitive vision, it has a ‘sunshield’ that’s the size of a tennis court; it gives the telescope the equivalent of SPF protection of 1 million! The sunshield also reduces the temperature between the hot and cold side of the spacecraft by almost 600 degrees Fahrenheit.

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8.  Webb’s 18-segment primary mirror is over 6 times bigger in area than Hubble's and will be ~100x more powerful. (How big is it? 6.5 meters in diameter.)

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9.  Webb’s 18 primary mirror segments can each be individually adjusted to work as one massive mirror. They’re covered with a golf ball's worth of gold, which optimizes them for reflecting infrared light (the coating is so thin that a human hair is 1,000 times thicker!).

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10. Webb will be so sensitive, it could detect the heat signature of a bumblebee at the distance of the moon, and can see details the size of a US penny at the distance of about 40 km.

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BONUS!  Over 1,200 scientists, engineers and technicians from 14 countries (and more than 27 U.S. states) have taken part in designing and building Webb. The entire project is a joint mission between NASA and the European and Canadian Space Agencies. The telescope part of the observatory was assembled in the world’s largest cleanroom at our Goddard Space Flight Center in Maryland.

Webb is currently at Northrop Grumman where the telescope will be mated with the spacecraft and undergo final testing. Once complete, Webb will be packed up and be transported via boat to its launch site in French Guiana, where a European Space Agency Ariane 5 rocket will take it into space.

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Learn more about the James Webb Space Telescope HERE, or follow the mission on Facebook, Twitter and Instagram.

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7 years ago

Five Famous Pulsars from the Past 50 Years

Early astronomers faced an obstacle: their technology. These great minds only had access to telescopes that revealed celestial bodies shining in visible light. Later, with the development of new detectors, scientists opened their eyes to other types of light like radio waves and X-rays. They realized cosmic objects look very different when viewed in these additional wavelengths. Pulsars — rapidly spinning stellar corpses that appear to pulse at us — are a perfect example.

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The first pulsar was observed 50 years ago on August 6, 1967, using radio waves, but since then we have studied them in nearly all wavelengths of light, including X-rays and gamma rays.

Typical Pulsar

Most pulsars form when a star — between 8 and 20 times the mass of our sun — runs out of fuel and its core collapses into a super dense and compact object: a neutron star. 

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These neutron stars are about the size of a city and can rotate slowly or quite quickly, spinning anywhere from once every few hours to hundreds of times per second. As they whirl, they emit beams of light that appear to blink at us from space.

First Pulsar

One day five decades ago, a graduate student at the University of Cambridge, England, named Jocelyn Bell was poring over the data from her radio telescope - 120 meters of paper recordings.

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Image Credit: Sumit Sijher

She noticed some unusual markings, which she called “scruff,” indicating a mysterious object (simulated above) that flashed without fail every 1.33730 seconds. This was the very first pulsar discovered, known today as PSR B1919+21.

Best Known Pulsar

Before long, we realized pulsars were far more complicated than first meets the eye — they produce many kinds of light, not only radio waves. Take our galaxy’s Crab Nebula, just 6,500 light years away and somewhat of a local celebrity. It formed after a supernova explosion, which crushed the parent star's core into a neutron star. 

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The resulting pulsar, nestled inside the nebula that resulted from the supernova explosion, is among the most well-studied objects in our cosmos. It’s pictured above in X-ray light, but it shines across almost the entire electromagnetic spectrum, from radio waves to gamma rays.

Brightest Gamma-ray Pulsar

Speaking of gamma rays, in 2015 our Fermi Gamma-ray Space Telescope discovered the first pulsar beyond our own galaxy capable of producing such high-energy emissions. 

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Located in the Tarantula Nebula 163,000 light-years away, PSR J0540-6919 gleams nearly 20 times brighter in gamma-rays than the pulsar embedded in the Crab Nebula.

Dual Personality Pulsar

No two pulsars are exactly alike, and in 2013 an especially fast-spinning one had an identity crisis. A fleet of orbiting X-ray telescopes, including our Swift and Chandra observatories, caught IGR J18245-2452 as it alternated between generating X-rays and radio waves. 

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Scientists suspect these radical changes could be due to the rise and fall of gas streaming onto the pulsar from its companion star.

Transformer Pulsar

This just goes to show that pulsars are easily influenced by their surroundings. That same year, our Fermi Gamma Ray Space Telescope uncovered another pulsar, PSR J1023+0038, in the act of a major transformation — also under the influence of its nearby companion star. 

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The radio beacon disappeared and the pulsar brightened fivefold in gamma rays, as if someone had flipped a switch to increase the energy of the system. 

NICER Mission

Our Neutron star Interior Composition Explorer (NICER) mission, launched this past June, will study pulsars like those above using X-ray measurements.

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With NICER’s help, scientists will be able to gaze even deeper into the cores of these dense and mysterious entities.

For more information about NICER, visit https://www.nasa.gov/nicer

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8 years ago

Largest Batch of Earth-size, Habitable Zone Planets

Our Spitzer Space Telescope has revealed the first known system of seven Earth-size planets around a single star. Three of these planets are firmly located in an area called the habitable zone, where liquid water is most likely to exist on a rocky planet.

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This exoplanet system is called TRAPPIST-1, named for The Transiting Planets and Planetesimals Small Telescope (TRAPPIST) in Chile. In May 2016, researchers using TRAPPIST announced they had discovered three planets in the system.

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Assisted by several ground-based telescopes, Spitzer confirmed the existence of two of these planets and discovered five additional ones, increasing the number of known planets in the system to seven.

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This is the FIRST time three terrestrial planets have been found in the habitable zone of a star, and this is the FIRST time we have been able to measure both the masses and the radius for habitable zone Earth-sized planets.

All of these seven planets could have liquid water, key to life as we know it, under the right atmospheric conditions, but the chances are highest with the three in the habitable zone.

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At about 40 light-years (235 trillion miles) from Earth, the system of planets is relatively close to us, in the constellation Aquarius. Because they are located outside of our solar system, these planets are scientifically known as exoplanets. To clarify, exoplanets are planets outside our solar system that orbit a sun-like star.

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In this animation, you can see the planets orbiting the star, with the green area representing the famous habitable zone, defined as the range of distance to the star for which an Earth-like planet is the most likely to harbor abundant liquid water on its surface. Planets e, f and g fall in the habitable zone of the star.

Using Spitzer data, the team precisely measured the sizes of the seven planets and developed first estimates of the masses of six of them. The mass of the seventh and farthest exoplanet has not yet been estimated.

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For comparison…if our sun was the size of a basketball, the TRAPPIST-1 star would be the size of a golf ball.

Based on their densities, all of the TRAPPIST-1 planets are likely to be rocky. Further observations will not only help determine whether they are rich in water, but also possibly reveal whether any could have liquid water on their surfaces.

The sun at the center of this system is classified as an ultra-cool dwarf and is so cool that liquid water could survive on planets orbiting very close to it, closer than is possible on planets in our solar system. All seven of the TRAPPIST-1 planetary orbits are closer to their host star than Mercury is to our sun.

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 The planets also are very close to each other. How close? Well, if a person was standing on one of the planet’s surface, they could gaze up and potentially see geological features or clouds of neighboring worlds, which would sometimes appear larger than the moon in Earth’s sky.

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The planets may also be tidally-locked to their star, which means the same side of the planet is always facing the star, therefore each side is either perpetual day or night. This could mean they have weather patterns totally unlike those on Earth, such as strong wind blowing from the day side to the night side, and extreme temperature changes.

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Because most TRAPPIST-1 planets are likely to be rocky, and they are very close to one another, scientists view the Galilean moons of Jupiter – lo, Europa, Callisto, Ganymede – as good comparisons in our solar system. All of these moons are also tidally locked to Jupiter. The TRAPPIST-1 star is only slightly wider than Jupiter, yet much warmer. 

How Did the Spitzer Space Telescope Detect this System?

Spitzer, an infrared telescope that trails Earth as it orbits the sun, was well-suited for studying TRAPPIST-1 because the star glows brightest in infrared light, whose wavelengths are longer than the eye can see. Spitzer is uniquely positioned in its orbit to observe enough crossing (aka transits) of the planets in front of the host star to reveal the complex architecture of the system. 

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Every time a planet passes by, or transits, a star, it blocks out some light. Spitzer measured the dips in light and based on how big the dip, you can determine the size of the planet. The timing of the transits tells you how long it takes for the planet to orbit the star.

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The TRAPPIST-1 system provides one of the best opportunities in the next decade to study the atmospheres around Earth-size planets. Spitzer, Hubble and Kepler will help astronomers plan for follow-up studies using our upcoming James Webb Space Telescope, launching in 2018. With much greater sensitivity, Webb will be able to detect the chemical fingerprints of water, methane, oxygen, ozone and other components of a planet’s atmosphere.

At 40 light-years away, humans won’t be visiting this system in person anytime soon...that said...this poster can help us imagine what it would be like: 

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9 years ago

A Spacecraft's Second Life: Our K2 mission

A critical failure that ended one mission has borne an unexpected and an exciting new science opportunity. The Kepler spacecraft, known for finding thousands of planets orbiting other stars, has a new job as the K2 mission.

Like its predecessor, K2 detects the tiny, telltale dips in the brightness of a star as an object passes or transits it, to possibly reveal the presence of a planet. Searching close neighboring stars for near-Earth-sized planets, K2 is finding planets ripe for follow-up studies on their atmospheres and to see what the planet is made of. A step up from its predecessor, K2 is revealing new info on comets, asteroids, dwarf planets, ice giants and moons. It will also provide new insight into areas as diverse as the birth of new stars, how stars explode into spectacular supernovae, and even the evolution of black holes.

K2 is expanding the planet-hunting legacy and has ushered in entirely new opportunities in astrophysics research, yet this is only the beginning.

Searching Nearby for Signs of Life

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Image credit: ESO/L. Calçada

Scientists are excited about nearby multi-planet system known as K2-3. This planetary system, discovered by K2, is made of three super-Earth-sized planets orbiting a cool M-star (or red dwarf) 135 light-years away, which is relatively close in astronomical terms. To put that distance into perspective, if the Milky Way galaxy was scaled down to the size of the continental U.S. it would be the equivalent of walking the three-mile long Golden Gate Park in San Francisco, California. At this distance, our other powerful space-investigators – the Hubble Space Telescope and the forthcoming James Webb Space Telescope (JWST) – could study the atmospheres of these worlds in search of chemical fingerprints that could be indicative of life. K2 expects to find a few hundred of these close-by, near-Earth-sized neighbors.

K2 won’t be alone in searching for nearby planets outside our solar system. Revving up for launch around 2017-2018, our Transiting Exoplanet Survey Satellite (TESS) plans to monitor 200,000 close stars for planets, with a focus on finding Earth and Super-Earth-sized planets.

The above image is an artist rendering of Gliese 581, a planetary system representative of K2-3.

Neptune's Moon Dance

Movie credit: NASA Ames/SETI Institute/J. Rowe

Spying on our neighbors in our own solar system, K2 caught Neptune in a dance with its moons Triton and Nereid. On day 15 (day counter located in the top right-hand corner of the green frame) of the sped-up movie, Neptune appears, followed by its moon Triton, which looks small and faint. Keen-eyed observers can also spot Neptune's tiny moon Nereid at day 24. Neptune is not moving backward but appears to do so because of the changing position of the Kepler spacecraft as it orbits around the sun. A few fast-moving asteroids make cameo appearances in the movie, showing up as streaks across the K2 field of view. The red dots are a few of the stars K2 examines in its search for transiting planets outside of our solar system. An international team of astronomers is using these data to track Neptune’s weather and probe the planet’s internal structure by studying subtle brightness fluctuations that can only be observed with K2.

Dead Star Devours Planet

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Image credit: CfA/Mark A. Garlick

K2 also caught a white dwarf – the dead core of an exploded star –vaporizing a nearby tiny rocky planet. Slowly the planet will disintegrate, leaving a dusting of metals on the surface of the star. This trail of debris blocks a tiny fraction of starlight from the vantage point of the spacecraft producing an unusual, but vaguely familiar pattern in the data. Recognizing the pattern, scientists further investigated the dwarf’s atmosphere to confirm their find. This discovery has helped validate a long-held theory that white dwarfs are capable of cannibalizing possible remnant planets that have survived within its solar system.

Searching for Far Out Worlds

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NASA/JPL-Caltech

In April, spaced-based K2 and ground-based observatories on five continents will participate in a global experiment in exoplanet observation and simultaneously monitor the same region of sky towards the center of our galaxy to search for small planets, such as the size of Earth, orbiting very far from their host star or, in some cases, orbiting no star at all. For this experiment, scientists will use gravitational microlensing – the phenomenon that occurs when the gravity of a foreground object focuses and magnifies the light from a distant background star.

The animation demonstrates the principles of microlensing. The observer on Earth sees the source (distant) star when the lens (closer) star and planet pass through the center of the image. The inset shows what may be seen through a ground-based telescope. The image brightens twice, indicating when the star and planet pass through the observatory's line of sight to the distant star.

Full microlensing animation available HERE.

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9 years ago

A Wider Set of Eyes on the Universe

After years of preparatory studies, we are formally starting an astrophysics mission designed to help unlock the secrets of the universe. 

Introducing…

the Wide Field Infrared Survey Telescope, aka WFIRST.

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With a view 100 times bigger than that of our Hubble Space Telescope, WFIRST will help unravel the secrets of dark energy and dark matter, and explore the evolution of the cosmos. It will also help us discover new worlds and advance the search for planets suitable for life.

WFIRST is slated to launch in the mid-2020s. The observatory will begin operations after traveling about one million miles from Earth, in a direction directly opposite the sun.

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Telescopes usually come in two different “flavors” - you have really big, powerful telescopes, but those telescopes only see a tiny part of the sky. Or, telescopes are smaller and so they lack that power, but they can see big parts of the sky. WFIRST is the best of worlds.

No matter how good a telescope you build, it’s always going to have some residual errors. WFIRST will be the first time that we’re going to fly an instrument that contains special mirrors that will allow us to correct for errors in the telescope. This has never been done in space before!

Employing multiple techniques, astronomers will also use WFIRST to track how dark energy and dark matter have affected the evolution of our universe. Dark energy is a mysterious, negative pressure that has been speeding up the expansion of the universe. Dark matter is invisible material that makes up most of the matter in our universe.

Single WFIRST images will contain over a million galaxies! We can’t categorize and catalogue those galaxies on our own, which is where citizen science comes in. This allows interested people in the general public to solve scientific problems.

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