Galaxies - Blog Posts

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I’ve just realized I never posted this art right here

I HAVE MADE ALL THOSE STARS YOU SEEING

ONE.

BY.

ONE.

It took me so much work, but it was worthy as fck

My Expression Of A Girl's Perspective. "We all fear the dark, but without it, we wouldn't be able to see the beauty of a whole galaxy."

Love Letters from Space

Love is in the air, and it’s out in space too! The universe is full of amazing chemistry, cosmic couples held together by gravitational attraction, and stars pulsing like beating hearts.

Celestial objects send out messages we can detect if we know how to listen for them. Our upcoming Nancy Grace Roman Space Telescope will help us scour the skies for all kinds of star-crossed signals.

Celestial Conversation Hearts

Communication is key for any relationship – including our relationship with space. Different telescopes are tuned to pick up different messages from across the universe, and combining them helps us learn even more. Roman is designed to see some visible light – the type of light our eyes can see, featured in the photo above from a ground-based telescope – in addition to longer wavelengths, called infrared. That will help us peer through clouds of dust and across immense stretches of space.

Other telescopes can see different types of light, and some detectors can even help us study cosmic rays, ghostly neutrinos, and ripples in space called gravitational waves.

Intergalactic Hugs

This visible and near-infrared image from the Hubble Space Telescope captures two hearts locked in a cosmic embrace. Known as the Antennae Galaxies, this pair’s love burns bright. The two spiral galaxies are merging together, igniting the birth of brand new baby stars.

Stellar nurseries are often very dusty places, which can make it hard to tell what’s going on. But since Roman can peer through dust, it will help us see stars in their infancy. And Roman’s large view of space coupled with its sharp, deep imaging will help us study how galaxy mergers have evolved since the early universe.

Cosmic Chemistry

Those stars are destined to create new chemistry, forging elements and scattering them into space as they live, die, and merge together. Roman will help us understand the cosmic era when stars first began forming. The mission will help scientists learn more about how elements were created and distributed throughout galaxies.

Did you know that U and I (uranium and iodine) were both made from merging neutron stars? Speaking of which…

Fatal Attraction

When two neutron stars come together in a marriage of sorts, it creates some spectacular fireworks! While they start out as stellar sweethearts, these and some other types of cosmic couples are fated for devastating breakups.

When a white dwarf – the leftover core from a Sun-like star that ran out of fuel – steals material from its companion, it can throw everything off balance and lead to a cataclysmic explosion. Studying these outbursts, called type Ia supernovae, led to the discovery that the expansion of the universe is speeding up. Roman will scan the skies for these exploding stars to help us figure out what’s causing the expansion to accelerate – a mystery known as dark energy.

Going Solo

Plenty of things in our galaxy are single, including hundreds of millions of stellar-mass black holes and trillions of “rogue” planets. These objects are effectively invisible – dark objects lost in the inky void of space – but Roman will see them thanks to wrinkles in space-time.

Anything with mass warps the fabric of space-time. So when an intervening object nearly aligns with a background star from our vantage point, light from the star curves as it travels through the warped space-time around the nearer object. The object acts like a natural lens, focusing and amplifying the background star’s light.

Thanks to this observational effect, which makes stars appear to temporarily pulse brighter, Roman will reveal all kinds of things we’d never be able to see otherwise.

Roman is nearly ready to set its sights on so many celestial spectacles. Follow along with the mission’s build progress in this interactive virtual tour of the observatory, and check out these space-themed Valentine’s Day cards.

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

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.

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.

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.

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.

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. 

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. 

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

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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.

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.

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.

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.

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Black Hole Friday Deals!

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!

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 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.

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.

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.

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…

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.

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.

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!

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)!

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.

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.

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.

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.

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.

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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.

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.

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.

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.

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.

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!

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.

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.

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.

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!

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.

Stay tuned to NASA Universe on Twitter and Facebook to keep up with what’s going on in the cosmos every day. You can learn more about the universe here.

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Scary Space Stories to Tell in the Dark

The universe is full of dazzling sights, but there’s an eerie side of space, too. Nestled between the stars, shadowy figures lurk unseen. The entire galaxy could even be considered a graveyard, full of long-dead stars. And it’s not just the Milky Way – the whole universe is a bit like one giant haunted house! Our Nancy Grace Roman Space Telescope will illuminate all kinds of spine-chilling cosmic mysteries when it launches in 2027, but for now settle in for some true, scary space stories.

Flickering Lights

One of the first signs that things are about to get creepy in a scary movie is when the lights start to flicker. That happens all the time in space, too! But instead of being a sinister omen, it can help us find planets circling other stars.

Roman will stare toward the heart of our galaxy and watch to see when pairs of stars appear to align in the sky. When that happens, the nearer star – and orbiting planets – can lens light from the farther star, creating a brief brightening. That’s because every massive object warps the fabric of space-time, changing the path light takes when it passes close by. Roman could find around 1,000 planets using this technique, which is called microlensing.

The mission will also see little flickers when planets cross in front of their host star as they orbit and temporarily dim the light we receive from the star. Roman could find an additional 100,000 planets this way!

Galactic Ghosts

Roman is going to be one of the best ghost hunters in the galaxy! Since microlensing relies on an object’s gravity, not its light, it can find all kinds of invisible specters drifting through the Milky Way. That includes rogue planets, which roam the galaxy alone instead of orbiting a star…

…and solo stellar-mass black holes, which we can usually only find when they have a visible companion, like a star. Astronomers think there should be 100 million of these black holes in our galaxy.

Stellar Skeletons

Black holes aren’t the only dead stars hiding in the sky. When stars that aren’t quite massive enough to form black holes run out of fuel, they blast away their outer layers and become neutron stars. These stellar cores are the densest material we can directly observe. One sugar cube of neutron star material would weigh about 1 billion tons (or 1 trillion kilograms) on Earth! Roman will be able to detect when these extreme objects collide.

Smaller stars like our Sun have less dramatic fates. After they run out of fuel, they swell up and shrug off their outer layers until only a small, hot core called a white dwarf remains. Those outer layers may be recycled into later generations of stars and planets. Roman will explore regions where new stars are bursting to life, possibly containing the remnants of such dead stars.

Cosmic Cobwebs

If we zoom out far enough, the structure of space looks like a giant cobweb! The cosmic web is the large-scale backbone of the universe, made up mainly of a mysterious substance known as dark matter and laced with gas, upon which galaxies are built. Roman will find precise distances for more than 10 million galaxies to map the structure of the cosmos, helping astronomers figure out why the expansion of the universe is speeding up.

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

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You Are Made of Stardust

Though the billions of people on Earth may come from different areas, we share a common heritage: we are all made of stardust! From the carbon in our DNA to the calcium in our bones, nearly all of the elements in our bodies were forged in the fiery hearts and death throes of stars.

The building blocks for humans, and even our planet, wouldn’t exist if it weren’t for stars. If we could rewind the universe back almost to the very beginning, we would just see a sea of hydrogen, helium, and a tiny bit of lithium.

The first generation of stars formed from this material. There’s so much heat and pressure in a star’s core that they can fuse atoms together, forming new elements. Our DNA is made up of carbon, hydrogen, oxygen, nitrogen, and phosphorus. All those elements (except hydrogen, which has existed since shortly after the big bang) are made by stars and released into the cosmos when the stars die.

Each star comes with a limited fuel supply. When a medium-mass star runs out of fuel, it will swell up and shrug off its outer layers. Only a small, hot core called a white dwarf is left behind. The star’s cast-off debris includes elements like carbon and nitrogen. It expands out into the cosmos, possibly destined to be recycled into later generations of stars and planets. New life may be born from the ashes of stars.

Massive stars are doomed to a more violent fate. For most of their lives, stars are balanced between the outward pressure created by nuclear fusion and the inward pull of gravity. When a massive star runs out of fuel and its nuclear processes die down, it completely throws the star out of balance. The result? An explosion!

Supernova explosions create such intense conditions that even more elements can form. The oxygen we breathe and essential minerals like magnesium and potassium are flung into space by these supernovas.

Supernovas can also occur another way in binary, or double-star, systems. When a white dwarf steals material from its companion, it can throw everything off balance too and lead to another kind of cataclysmic supernova. Our Nancy Grace Roman Space Telescope will study these stellar explosions to figure out what’s speeding up the universe’s expansion. 

This kind of explosion creates calcium – the mineral we need most in our bodies – and trace minerals that we only need a little of, like zinc and manganese. It also produces iron, which is found in our blood and also makes up the bulk of our planet’s mass!

A supernova will either leave behind a black hole or a neutron star – the superdense core of an exploded star. When two neutron stars collide, it showers the cosmos in elements like silver, gold, iodine, uranium, and plutonium.

Some elements only come from stars indirectly. Cosmic rays are nuclei (the central parts of atoms) that have been boosted to high speed by the most energetic events in the universe. When they collide with atoms, the impact can break them apart, forming simpler elements. That’s how we get boron and beryllium – from breaking star-made atoms into smaller ones.

Half a dozen other elements are created by radioactive decay. Some elements are radioactive, which means their nuclei are unstable. They naturally break down to form simpler elements by emitting radiation and particles. That’s how we get elements like radium. The rest are made by humans in labs by slamming atoms of lighter elements together at super high speeds to form heavier ones. We can fuse together elements made by stars to create exotic, short-lived elements like seaborgium and einsteinium.

From some of the most cataclysmic events in the cosmos comes all of the beauty we see here on Earth. Life, and even our planet, wouldn’t have formed without them! But we still have lots of questions about these stellar factories. 

In 2006, our Stardust spacecraft returned to Earth containing tiny particles of interstellar dust that originated in distant stars, light-years away – the first star dust to ever be collected from space and returned for study. You can help us identify and study the composition of these tiny, elusive particles through our Stardust@Home Citizen Science project.

Our upcoming Roman Space Telescope will help us learn more about how elements were created and distributed throughout galaxies, all while exploring many other cosmic questions. Learn more about the exciting science this mission will investigate on Twitter and Facebook.

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Space is a Dusty Place!

Butterfly Nebula

When you look at pictures of space, do you know what you’re actually seeing? A lot of the time the answer is dust!

HII region seen by Chandra X-ray Observatory

Clouds of dust drift through our galaxy. Telescopes can take pictures of these clouds when stars light them up. Who knew dust could be so beautiful? But it’s more than just pretty – we can learn a lot from it, too!

Stars like our Sun are born in dust clouds. Over time, leftover dust clumps together to help form planets. That makes it a little less dusty.

At certain times of the year, a band of sun-reflecting dust from the inner Solar System appears prominently just after sunset -- or just before sunrise -- and is called zodiacal light. Credit: Ruslan Merzlyakov/astrorms

But later, objects like comets and asteroids can create new dust by breaking up into tiny rocks. In our solar system, these rocky grains are called zodiacal dust. That’s because it’s mostly visible near the constellations of the zodiac. We can see the hazy glow it creates just after sunset or shortly before dawn sometimes, like in the picture above.

Around other stars, it’s called exozodiacal dust. Try saying that five times fast! It makes it hazy there too, so it can be hard to see distant planets.

Our Nancy Grace Roman Space Telescope will be really good at seeing how much of this dust is swirling around nearby stars. That will help future telescopes know the best places to look to find planets like Earth!

Roman will also see more distant objects. It will peer inside dust clouds where new stars are bursting into life. That will help our James Webb Space Telescope know where to look to find baby planets. Webb can zoom in for a more detailed look at these young worlds by seeing how they filter their host star’s light.

Roman will see huge patches of the sky – much bigger than our Hubble and Webb telescopes can see. These missions will team up to explore all kinds of cosmic mysteries!

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

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Roman’s Family Portrait of Millions of Galaxies

About 15 years ago, our Hubble Space Telescope captured this ultra-deep field image of space, revealing thousands of galaxies tucked away in a seemingly empty spot in the sky.

Now, imagine this view of the cosmos – and all the mysteries in it – at a scale 300 times larger than Hubble's.

Our upcoming Nancy Grace Roman Telescope could capture just that.

Roman recently released this gorgeous simulated image that gives us a preview of what the telescope could see. Each tiny speck represents a galaxy filled with billions of stars. And it’s more than just a pretty picture – scientists could learn a lot from an observation like this!

Since Roman can see much more of the sky at a time, it could create an ultra-deep field image that’s far larger than Hubble’s. So instead of revealing thousands of galaxies, Roman would see millions!

Roman’s ability to look far out into space with such an expansive view would help us better understand what the universe was like when it was young. For example, scientists could study a lot of cosmic transitions, like how galaxies switch from star-making factories to a quieter stage when star formation is complete and how the universe went from being mainly opaque to the brilliant starscape we see today.

And these are just a few of the mysteries Roman could help us solve!

Set to launch in the mid-2020s, our Nancy Grace Roman Space Telescope, is designed to unravel the secrets of dark energy and dark matter, search for and image exoplanets, and explore many topics in infrared astrophysics. You can learn about some of the other science Roman will do here.

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How exactly will it work? And whats the goal of the project?

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

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!

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?

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.

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

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

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

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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How will the James Webb Space Telescope change how we see the universe? Ask an expert!

The James Webb Space Telescope is launching on December 22, 2021. Webb’s revolutionary technology will explore every phase of cosmic history—from within our solar system to the most distant observable galaxies in the early universe, to everything in between. Postdoctoral Research Associate Naomi Rowe-Gurney will be taking your questions about Webb and Webb science in an Answer Time session on Tuesday, December 14 from noon to 1 p.m EST here on our Tumblr!

🚨 Ask your questions now by visiting http://nasa.tumblr.com/ask.

Dr. Naomi Rowe-Gurney recently completed her PhD at the University of Leicester and is now working at NASA Goddard Space Flight Center as a postdoc through Howard University. As a planetary scientist for the James Webb Space Telescope, she’s an expert on the atmospheres of the ice giants in our solar system — Uranus and Neptune — and how the Webb telescope will be able to learn more about them.

The James Webb Space Telescope – fun facts:

Webb is so big it has to fold origami-style to fit into its rocket and will unfold like a “Transformer” in space.

Webb is about 100 times more powerful than the Hubble Space Telescope and designed to see the infrared, a region Hubble can only peek at.

With unprecedented sensitivity, it will peer back in time over 13.5 billion years to see the first galaxies born after the Big Bang––a part of space we’ve never seen.

It will study galaxies near and far, young and old, to understand how they evolve.

Webb will explore distant worlds and study the atmospheres of planets orbiting other stars, known as exoplanets, searching for chemical fingerprints of possible habitability.

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Dark Energy

This bone-chilling force will leave you shivering alone in terror! An unseen power is prowling throughout the cosmos, driving the universe to expand at a quickening rate. This relentless pressure, called dark energy, is nothing like dark matter, that mysterious material revealed only by its gravitational pull. Dark energy offers a bigger fright: pushing galaxies farther apart over trillions of years, leaving the universe to an inescapable, freezing death in the pitch black expanse of outer space. Download this free poster in English and Spanish and check out the full Galaxy of Horrors.

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Our Galaxy is Caught Up in a Giant Cosmic Cobweb! 🕸️

If we could zoom waaaay out, we would see that galaxies and galaxy clusters make up large, fuzzy threads, like the strands of a giant cobweb. But we'll work our way out to that. First let's start at home and look at our planet's different cosmic communities.

Our home star system

Earth is one of eight planets — Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune — that orbit the Sun. But our solar system is more than just planets; it also has a lot of smaller objects.

An asteroid belt circles the Sun between Mars and Jupiter. Beyond Neptune is a doughnut-shaped region of icy objects called the Kuiper Belt. This is where dwarf planets like Pluto and Makemake are found and is likely the source of short-period comets (like Haley’s comet), which orbit the Sun in less than 200 years.

Scientists think that even farther out lies the Oort Cloud, also a likely source of comets. This most distant region of our solar system is a giant spherical shell storing additional icy space debris the size of mountains, or larger! The outer edge of the Oort Cloud extends to about 1.5 light-years from the Sun — that’s the distance light travels in a year and a half (over 9 trillion miles).

Sometimes asteroids or comets get ejected from these regions and end up sharing an orbit with planets like Jupiter or even crossing Earth’s orbit. There are even interstellar objects that have entered the inner solar system from even farther than the Oort Cloud, perhaps coming all the way from another star!

Our home galaxy

Let's zoom out to look at the whole Milky Way galaxy, which contains more than 100 billion stars. Many are found in the galaxy’s disk — the pancake-shaped part of a spiral galaxy where the spiral arms lie. The brightest and most massive stars are found in the spiral arms, close to their birth places. Dimmer, less massive stars can be found sprinkled throughout the disk. Also found throughout the spiral arms are dense clouds of gas and dust called nebulae. The Sun lies in a small spiral arm called the Orion Spur.

The Milky Way’s disk is embedded in a spherical “halo” about 120,000 light-years across. The halo is dotted with globular clusters of old stars and filled with dark matter. Dark matter doesn’t emit enough light for us to directly detect it, but we know it’s there because without its mass our galaxy doesn’t have enough gravity to hold together!

Our galaxy also has several orbiting companion galaxies ranging from about 25,000 to 1.4 million light-years away. The best known of these are the Large and Small Magellanic Clouds, which are visible to the unaided eye from Earth’s Southern Hemisphere.

Our galactic neighborhood

The Milky Way and Andromeda, our nearest neighboring spiral galaxy, are just two members of a small group of galaxies called the Local Group. They and the other members of the group, 50 to 80 smaller galaxies, spread across about 10 million light-years.

The Local Group lies at the outskirts of an even larger structure. It is just one of at least 100 groups and clusters of galaxies that make up the Virgo Supercluster. This cluster of clusters spans about 110 million light-years!

Galaxies aren’t the only thing found in a galaxy cluster, though. We also find hot gas, as shown above in the bright X-ray light (in pink) that surrounds the galaxies (in optical light) of cluster Abell 1413, which is a picturesque member of a different supercluster. Plus, there is dark matter throughout the cluster that is only detectable through its gravitational interactions with other objects.

The Cosmic Web

The Virgo Supercluster is just one of many, many other groups of galaxies. But the universe’s structure is more than just galaxies, clusters, and the stuff contained within them.

For more than two decades, astronomers have been mapping out the locations of galaxies, revealing a filamentary, web-like structure. This large-scale backbone of the cosmos consists of dark matter laced with gas. Galaxies and clusters form along this structure, and there are large voids in between.

The scientific visualizations of this “cosmic web” look a little like a spider web, but that would be one colossal spider! <shudder>

And there you have the different communities that define Earth’s place in the universe. Our tiny planet is a small speck on a crumb of that giant cosmic web!

Want to learn even more about the structures in the universe? Check out our Cosmic Distance Scale!

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Discovering the Universe Through the Constellation Orion

Do you ever look up at the night sky and get lost in the stars? Maybe while you’re stargazing, you spot some of your favorite constellations. But did you know there’s more to constellations than meets the eye? They’re not just a bunch of imaginary shapes made up of stars — constellations tell us stories about the universe from our perspective on Earth.

What is a constellation?

A constellation is a named pattern of stars that looks like a particular shape. Think of it like connecting the dots. If you join the dots — stars, in this case — and use your imagination, the picture would look like an object, animal, or person. For example, the ancient Greeks believed an arrangement of stars in the sky looked like a giant hunter with a sword attached to his belt, so they named it after a famous hunter in their mythology, Orion. It’s one of the most recognizable constellations in the night sky and can be seen around the world. The easiest way to find Orion is to go outside on a clear night and look for three bright stars close together in an almost-straight line. These three stars represent Orion's belt. Two brighter stars to the north mark his shoulders, and two more to the south represent his feet.

Credit: NASA/STScI

Over time, cultures around the world have had different names and numbers of constellations depending on what people thought they saw. Today, there are 88 officially recognized constellations. Though these constellations are generally based on what we can see with our unaided eyes, scientists have also invented unofficial constellations for objects that can only be seen in gamma rays, the highest-energy form of light.

Perspective is everything

The stars in constellations may look close to each other from our point of view here on Earth, but in space they might be really far apart. For example, Alnitak, the star at the left side of Orion's belt, is about 800 light-years away. Alnilam, the star in the middle of the belt, is about 1,300 light-years away. And Mintaka, the star at the right side of the belt, is about 900 light-years away. Yet they all appear from Earth to have the same brightness. Space is three-dimensional, so if you were looking at the stars that make up the constellation Orion from another part of our galaxy, you might see an entirely different pattern!

The superstars of Orion

Now that we know a little bit more about constellations, let’s talk about the supercool cosmic objects that form them – stars! Though over a dozen stars make up Orion, two take center stage. The red supergiant Betelgeuse (Orion's right shoulder) and blue supergiant Rigel (Orion's left foot) stand out as the brightest members in the constellation.

Credit: Derrick Lim

Betelgeuse is a young star by stellar standards, about 10 million years old, compared to our nearly 5 billion-year-old Sun. The star is so huge that if it replaced the Sun at the center of our solar system, it would extend past the main asteroid belt between Mars and Jupiter! But due to its giant mass, it leads a fast and furious life.

Betelgeuse is destined to end in a supernova blast. Scientists discovered a mysterious dimming of Betelgeuse in late 2019 caused by a traumatic outburst that some believed was a precursor to this cosmic event. Though we don’t know if this incident is directly related to an imminent supernova, there’s a tiny chance it might happen in your lifetime. But don't worry, Betelgeuse is about 550 light-years away, so this event wouldn't be dangerous to us – but it would be a spectacular sight.

Rigel is also a young star, estimated to be 8 million years old. Like Betelgeuse, Rigel is much larger and heavier than our Sun. Its surface is thousands of degrees hotter than Betelgeuse, though, making it shine blue-white rather than red. These colors are even noticeable from Earth. Although Rigel is farther from Earth than Betelgeuse (about 860 light-years away), it is intrinsically brighter than its companion, making it the brightest star in Orion and one of the brightest stars in the night sky.

Credit: Rogelio Bernal Andreo

Buckle up for Orion’s belt

Some dots that make up constellations are actually more than one star, but from a great distance they look like a single object. Remember Mintaka, the star at the far right side of Orion's belt? It is not just a single star, but actually five stars in a complex star system.

Credit: X-ray: NASA/CXC/GSFC/M. Corcoran et al.; Optical: Eckhard Slawik

Sword or a stellar nursery?

Below the three bright stars of Orion’s belt lies his sword, where you can find the famous Orion Nebula. The nebula is only 1,300 light-years away, making it the closest large star-forming region to Earth. Because of its brightness and prominent location just below Orion’s belt, you can actually spot the Orion Nebula from Earth! But with a pair of binoculars, you can get a much more detailed view of the stellar nursery. It’s best visible in January and looks like a fuzzy “star” in the middle of Orion’s sword.

More to discover in constellations

In addition to newborn stars, Orion also has some other awesome cosmic objects hanging around. Scientists have discovered exoplanets, or planets outside of our solar system, orbiting stars there. One of those planets is a giant gas world three times more massive than Jupiter. It’s estimated that on average there is at least one planet for every star in our galaxy. Just think of all the worlds you may be seeing when you look up at the night sky!

It’s also possible that the Orion Nebula might be home to a black hole, making it the closest known black hole to Earth. Though we may never detect it, because no light can escape black holes, making them invisible. However, space telescopes with special instruments can help find black holes. They can observe the behavior of material and stars that are very close to black holes, helping scientists find clues that can lead them closer to discovering some of these most bizarre and fascinating objects in the cosmos.

Next time you go stargazing, remember that there’s more to the constellations than meets the eye. Let them guide you to some of the most incredible and mysterious objects of the cosmos — young stars, brilliant nebulae, new worlds, star systems, and even galaxies!

To keep up with the most recent stellar news, follow NASA Universe on Twitter and Facebook.

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Hubble’s Guide to Viewing Deep Fields

They say a picture is worth a thousand words, but no images have left a greater impact on our understanding of the universe quite like the Hubble Space Telescope’s deep fields. Like time machines, these iconic images transport humanity billions of light-years back in time, offering a glimpse into the early universe and insight into galaxy evolution!

You’ve probably seen these images before, but what exactly do we see within them? Deep field images are basically core samples of our universe. By peering into a small portion of the night sky, we embark on a journey through space and time as thousands of galaxies appear before our very eyes.

So, how can a telescope the size of a school bus orbiting 340 miles above Earth uncover these mind-boggling galactic masterpieces? We’re here to break it down. Here’s Hubble’s step-by-step guide to viewing deep fields:

Step 1: Aim at the darkness

Believe it or not, capturing the light of a thousand galaxies actually begins in the dark. To observe extremely faint galaxies in the farthest corners of the cosmos, we need minimal light interference from nearby stars and other celestial objects. The key is to point Hubble’s camera at a dark patch of sky, away from the outer-edge glow of our own galaxy and removed from the path of our planet, the Sun, or the Moon. This “empty” black canvas of space will eventually transform into a stunning cosmic mosaic of galaxies.

The first deep field image was captured in 1995. In order to see far beyond nearby galaxies, Hubble’s camera focused on a relatively empty patch of sky within the constellation Ursa Major. The results were this step-shaped image, an extraordinary display of nearly 3,000 galaxies spread across billions of light-years, featuring some of the earliest galaxies to emerge shortly after the big bang.

Step 2: Take it all in

The universe is vast, and peering back billions of years takes time. Compared to Hubble’s typical exposure time of a few hours, deep fields can require hundreds of hours of exposure over several days. Patience is key. Capturing and combining several separate exposures allows astronomers to assemble a comprehensive core slice of our universe, providing key information about galaxy formation and evolution. Plus, by combining exposures from different wavelengths of light, astronomers are able to better understand galaxy distances, ages, and compositions.

The Hubble Ultra Deep Field is the deepest visible-light portrait of our universe. This astonishing display of nearly 10,000 galaxies was imaged over the course of 400 Hubble orbits around Earth, with a total of 800 exposures captured over 11.3 days.

Step 3: Go beyond what’s visible

The ability to see across billions of light-years and observe the farthest known galaxies in our universe requires access to wavelengths beyond those visible to the human eye. The universe is expanding and light from distant galaxies is stretched far across space, taking a long time to reach us here on Earth. This  phenomenon, known as “redshift,” causes longer wavelengths of light to appear redder the farther they have to travel through space. Far enough away, and the wavelengths will be stretched into infrared light. This is where Hubble’s infrared vision comes in handy. Infrared light allows us to observe light from some of the earliest galaxies in our universe and better understand the history of galaxy formation over time.

In 2009, Hubble observed the Ultra Deep Field in the infrared. Using the Near Infrared Camera and Multi-Object Spectrometer, astronomers gathered one of the deepest core samples of our universe and captured some of the most distant galaxies ever observed.

Step 4: Use your time machine

Apart from their remarkable beauty and impressive imagery, deep field images are packed with information, offering astronomers a cosmic history lesson billions of years back in time within a single portrait. Since light from distant galaxies takes time to reach us, these images allow astronomers to travel through time and observe these galaxies as they appear at various stages in their development. By observing Hubble’s deep field images, we can begin to discover the questions we’ve yet to ask about our universe.

Credit: NASA, ESA, R. Bouwens and G. Illingworth (University of California, Santa Cruz)

Hubble’s deep field images observe galaxies that emerged as far back as the big bang. This image of the Hubble Ultra Deep Field showcases 28 of over 500 early galaxies from when the universe was less than one billion years old. The light from these galaxies represent different stages in their evolution as their light travels through space to reach us.

Step 5: Expand the cosmic frontier

Hubble’s deep fields have opened a window to a small portion of our vast universe, and future space missions will take this deep field legacy even further. With advancements in technologies and scientific instruments, we will soon have the ability to further uncover the unimaginable.

Slated for launch in late 2021, NASA’s James Webb Space Telescope will offer a new lens to our universe with its impressive infrared capabilities. Relying largely on the telescope’s mid-infrared instrument, Webb will further study portions of the Hubble deep field images in greater detail, pushing the boundaries of the cosmic frontier even further.

And there you have it, Hubble’s guide to unlocking the secrets of the cosmos! To this day, deep field images remain fundamental building blocks for studying galaxy formation and deepening not only our understanding of the universe, but our place within it as well.

Still curious about Hubble Deep Fields? Explore more and follow along on Twitter, Facebook, and Instagram with #DeepFieldWeek!

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Roman’s Heat-Vision Eyes Are Complete!

Our Nancy Grace Roman Space Telescope team recently flight-certified all 24 of the detectors the mission needs. When Roman launches in the mid-2020s, the detectors will convert starlight into electrical signals, which will then be decoded into 300-megapixel images of huge patches of the sky. These images will help astronomers explore all kinds of things, from rogue planets and black holes to dark matter and dark energy.

Eighteen of the detectors will be used in Roman’s camera, while another six will be reserved as backups. Each detector has 16 million tiny pixels, so Roman’s images will be super sharp, like Hubble’s.

The image above shows one of Roman’s detectors compared to an entire cell phone camera, which looks tiny by comparison. The best modern cell phone cameras can provide around 12-megapixel images. Since Roman will have 18 detectors that have 16 million pixels each, the mission will capture 300-megapixel panoramas of space.

The combination of such crisp resolution and Roman’s huge view has never been possible on a space-based telescope before and will make the Nancy Grace Roman Space Telescope a powerful tool in the future.

Learn more about the Roman Space Telescope!

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Weird and Wonderful Irregular Galaxies

Spiral and elliptical galaxies seem neatly put together, but what happened to irregular galaxies? Irregular galaxies have one-of-a-kind shapes and many look like blobs! Why do they look the way they do? Astronomers think the uniqueness of these galaxies results from their interactions with other galaxies — like when they pass close to one another or even collide!

Looking back at the early universe with the help of our Hubble Space Telescope’s “deep field” observations, astronomers can peek at galaxies millions and billions of light-years away. They noticed that these far-away galaxies appear unusually messy, showing more star formation and mergers than galaxies closer to the Milky Way.

We also see irregular galaxies closer to home, though. Some may form when two galaxies pass close together in a near-miss. When this happens, their gravity pulls stars out of place in both galaxies, messing up the neat structure they originally had as spiral or elliptical galaxies. Think of it like this: you happen to have a pile of papers sitting at the edge of a table and when someone passes close by the papers become ruffled and may scatter everywhere! Even though the two galaxies never touched, gravity's effects leave them looking smeared or distorted.

Some irregular galaxies result from the collision between two galaxies. And while some of these look like a blob of stars and dust, others form dazzling ring galaxies! Scientists think these may be a product of collisions between small and large galaxies. These collisions cause ripples that disturb both galaxies, throwing dust, gas, and stars outward. When this happens, it pushes out a ring of material, causing gas clouds to collide and spark the birth of new stars. After just a few million years, stars larger than our Sun explode as supernovae, leaving neutron stars and black holes throughout the ring!

Not all galaxy collisions create irregular galaxies — our Milky Way spiral galaxy has gone through many mergers but has stayed intact! And for some interacting galaxies, being an irregular galaxy may just be a phase in their transformation. We’re observing them at a snapshot in time where things are messy, but they may eventually become neat and structured spirals and ellipticals.

Irregular galaxies are similar to each other, but unique and beautiful because of their different interactions, whether they’re just passing another galaxy or taking part in a dramatic collision. Keep up with NASA Universe on Facebook and Twitter where we post regularly about galaxies.

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New Rose-Colored Glasses for the Roman Space Telescope

Big news for our Nancy Grace Roman Space Telescope! Thanks to some new “shades” – an infrared filter that will help us see longer wavelengths of light – the mission will be able to spot water ice on objects in the outer solar system, see deeper into clouds of gas and dust, and peer farther across space. We’re gearing up for some super exciting discoveries!

Rocks on the rocks

You probably know that our solar system includes planets, the Sun, and the asteroid belt in between Mars and Jupiter – but did you know there’s another ‘belt’ of small objects out past Neptune? It’s called the Kuiper belt, and it’s home to icy bodies that were left over from when our solar system formed.

A lot of the objects there are like cosmic fossils – they haven’t changed much since they formed billions of years ago. Using its new filter, Roman will be able to see how much water ice they have because the ice absorbs specific wavelengths of infrared light, providing a “fingerprint” of its presence. This will give us a window into the solar system’s early days.

Upgraded heat vision

Clouds of dust and gas drift throughout our galaxy, sometimes blocking our view of the stars behind them. It’s hard for visible light to penetrate this dusty haze because the particles are the same size or even larger than the light’s wavelength. Since infrared light travels in longer waves, it hardly notices the tiny particles and can pass more easily through dusty regions.

With Roman’s new filter, we’ll be able to see through much thicker dust clouds than we could have without the upgrade. It’ll be much easier to study the structure of our home galaxy, the Milky Way.

Roman’s expanded view will also help us learn more about brown dwarfs – objects that are more massive than planets, but not massive enough to light up like stars. The mission will find them near the heart of the galaxy, where stars explode more often.

These star explosions, called supernovae, are so extreme that they create and disperse new elements. So near the center of the galaxy, there should be higher amounts of elements that aren’t as common farther away, where supernovae don’t happen as often.

Astronomers think that may affect how stars and planets form. Using the new filter, Roman will probe the composition of brown dwarfs to help us understand more.

Baby galaxies

Roman’s upgraded filter will also help us see farther across space. As light travels through our expanding universe, its wavelength becomes stretched. The longer it travels before reaching us, the longer its wavelength becomes. Roman will be able to see so far back that we could glimpse some of the first stars and galaxies that ever formed. Their light will be so stretched that it will mostly arrive as infrared instead of visible light.

We’re still not sure how the very first galaxies formed because we’ve found so few of these super rare and faint beasts. But Roman will have such a big view of the universe and sharp enough vision that it could help us find a lot more of them. Then astronomers can zoom in on them with missions like our James Webb Space Telescope for a closer look.

Roman will help us explore these cosmic questions and many more! Learn more about the mission here: https://roman.gsfc.nasa.gov/

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Galaxies: Cities of Stars

Galaxies are like cities made of oodles of stars, gas, and dust bound together by gravity. These beautiful cosmic structures come in many shapes and sizes. Though there are a slew of galaxies in the universe, there are only a few we can see with the unaided eye or backyard telescope.

How many types are out there, how’d so many of them wind up with weird names, and how many stars live inside them? Hold tight while we explore these cosmic metropolises.

Galaxies come in lots of different shapes, sizes, and colors. But astronomers have noticed that there are mainly three types: spiral, elliptical, and irregular.

Spiral galaxies, like our very own Milky Way, look similar to pinwheels! These galaxies tend to have a bulging center heavily populated by stars, with elongated, sparser arms of dust and stars that wrap around it. Usually, there’s a huge black hole hiding at the center, like the Milky Way’s Sagittarius A* (pronounced A-star). Our galactic neighbor, Andromeda (also known as Messier 31 or M31), is also a spiral galaxy!

Elliptical galaxies tend to be smooth spheres of gas, dust, and stars. Like spiral galaxies, their centers are typically bulges surrounded by a halo of stars (but minus the epic spiral arms). The stars in these galaxies tend to be spread out neatly throughout the galaxies and are some of the oldest stars in the universe! Messier 87 (M87) is one example of an elliptical galaxy. The supermassive black hole at its center was recently imaged by the Event Horizon Telescope.

Irregular galaxies are, well … a bit strange. They have one-of-a-kind shapes, and many just look like messy blobs. Astronomers think that irregular galaxies' uniqueness is a result of interactions with other galaxies, like collisions! Galaxies are so big, with so much distance between their stars, that even when they collide, their stars usually do not. Galaxy collisions have been important to the formation of our Milky Way and others. When two galaxies collide, clouds of gas, dust, and stars are violently thrown around, forming an entirely new, larger one! This could be the cause of some irregular galaxies seen today.

Now that we know the different types of galaxies, what about how many stars they contain? Galaxies can come in lots of different sizes, even among each type. Dwarf galaxies, the smallest version of spiral, elliptical, and irregular galaxies, are usually made up of 1,000 to billions of stars. Compared to our Milky Way’s 200 to 400 billion stars, the dwarf galaxy known as the Small Magellanic Cloud is tiny, with just a few hundred million stars! IC 1101, on the other hand, is one of the largest elliptical galaxies found so far, containing almost 100 trillion stars.

Ever wondered how galaxies get their names? Astronomers have a number of ways to name galaxies, like the constellations we see them in or what we think they resemble. Some even have multiple names!

A more formal way astronomers name galaxies is with two-part designations based on astronomical catalogs, published collections of astronomical objects observed by specific astronomers, observatories, or spacecraft. These give us cryptic names like M51 or Swift J0241.3-0816. Catalog names usually have two parts:

A letter, word, or short acronym that identifies a specific astronomical catalog.

A sequence of numbers and/or letters that uniquely identify the galaxy within that catalog.

For M51, the “M” comes from the Messier catalog, which Charles Messier started compiling in 1771, and the "51" is because it’s the 51st entry in that catalog. Swift J0241.3-0816 is a galaxy observed by the Swift satellite, and the numbers refer to its location in the sky, similar to latitude and longitude on Earth.

There’s your quick intro to galaxies, but there’s much more to learn about them. Keep up with NASA Universe on Facebook and Twitter where we post regularly about galaxies.

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Boo-tiful Ring Galaxies

A ghoulish secret lurks within each of these gorgeous galaxies. Their rings are dotted with stellar graveyards!

These objects are called ring galaxies, and scientists think most of them form in monster-sized crashes. Not just any galaxy collision will do the trick, though. To produce the treat of a ring, a smaller galaxy needs to ram through the center of a larger galaxy at just the perfect angle.

The collision causes ripples that disturb both galaxies. The gravitational shock causes dust, gas, and stars in the larger galaxy’s disk to rush outward. As this ring of material plows out from the galaxy’s center, gas clouds collide and trigger the birth of new stars.

In visible light, the blue areas in the galaxies’ rings show us where young, hot stars are growing up. Faint, pink regions around the ring mark stellar nurseries where even younger stars set hydrogen gas aglow.

The newborn stars come in a mix of sizes, from smaller ones like our Sun all the way up to huge stars with tens of times the Sun’s mass. And those massive stars live large!

While a star like our Sun will last many billions of years before running out of fuel, larger stars burn much brighter and faster. After just a few million years, the largest stars explode as supernovae. When massive stars die, they leave behind a stellar corpse, either a neutron star or black hole.

When we turn our X-ray telescopes to these ring galaxies, we see telltale signs of stellar remnants dotted throughout their ghostly circles. The purple dots in the X-ray image above are neutron stars or black holes that are siphoning off gas from a companion star, like a vampire. The gas reinvigorates stellar corpses, which heat up and emit X-rays. These gas-thirsty remains are beacons lighting the way to stellar graveyards.

Spiral galaxies — like our home galaxy, the Milky Way — have curved arms that appear to sweep out around a bright center. The dust and gas in those spiral arms press together, causing cycles of star formation that result in a more even mix of new stars and stellar corpses scattered throughout our galaxy. No creepy ring of stellar corpses here!  

To visit some other eerie places in the universe, check out the latest additions to the Galaxy of Horrors poster series and follow NASA Universe on Twitter and Facebook for news about black holes, neutron stars, galaxies, and all the amazing objects outside our solar system.

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