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When will we start seeing images from the James Webb telescope??
How exactly will it work? And whats the goal of the project?
Concerning the new telescope -out of curiosity- what is the maximum distance it can view planets, galaxies, objects, anything up to -in terms of common/metric measurement, and/or years (if applicable) etc.? -Rose
What does “chemical fingerprints” mean? What chemicals indicate possible life on other planets?
Questions coming up from….
@maybeinanotherworld: JWST IS HAPPENING! How are all of you feeling about this?
@Anonymous: How powerful is this telescope, exactly?
@Anonymous: Why are the mirrors on it yellow?
@foeofcolor: How long is this estimated to last for? Like how long will it be able to function in space by estimates?
Who's ready to #UnfoldTheUniverse? The James Webb Space Telescope Answer Time with expert Dr. Naomi Rowe-Gurney is LIVE! Stay tuned for talks about the science goals, capabilities, and hopes for the world's most powerful telescope. View ALL the answers HERE.
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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.
Make sure to follow us on Tumblr for your regular dose of space!
Ready for a virtual adventure through the Orion Nebula?
Suspended in space, the stars that reside in the Orion Nebula are scattered throughout a dramatic dust-and-gas landscape of plateaus, mountains, and valleys that are reminiscent of the Grand Canyon. This visualization uses visible and infrared views, combining images from the Hubble Space Telescope and the Spitzer Space Telescope to create a three-dimensional visualization.
Learn more about Hubble’s celebration of Nebula November and see new nebula images, here.
You can also keep up with Hubble on Twitter, Instagram, Facebook, and Flickr!
Visualization credits: NASA, ESA, and F. Summers, G. Bacon, Z. Levay, J. DePasquale, L. Hustak, L. Frattare, M. Robberto, M. Gennaro (STScI), R. Hurt (Caltech/IPAC), M. Kornmesser (ESA); Acknowledgement: A. Fujii, R. Gendler
Black Holes Dine on Stellar Treats!
See that tiny blob of light, circled in red? Doesn’t look like much, does it? But that blob represents a feast big enough to feed a black hole around 30 million times the mass of our Sun! Scientists call these kinds of stellar meals tidal disruption events, and they’re some of the most dramatic happenings in the cosmos.
Sometimes, an unlucky star strays too close to a black hole. The black hole’s gravity pulls on the star, causing it to stretch in one direction and squeeze in another. Then the star pulls apart into a stream of gas. This is a tidal disruption event. (If you’re worried about this happening to our Sun – don’t. The nearest black hole we know about is over 1,000 light-years away. And black holes aren’t wild space vacuums. They don’t go zipping around sucking up random stars and planets. So we’re pretty safe from tidal disruption events!)
The trailing part of the stream gets flung out of the system. The rest of the gas loops back around the black hole, forming a disk. The material circling in the disk slowly drifts inward toward the black hole’s event horizon, the point at which nothing – not even light – can escape. The black hole consumes the gas and dust in its disk over many years.
Sometimes the black hole only munches on a passing star – we call this a partial tidal disruption event. The star loses some of its gas, but its own gravity pulls it back into shape before it passes the black hole again. Eventually, the black hole will have nibbled away enough material that the star can’t reform and gets destroyed.
We study tidal disruptions, both the full feasts and the partial snacks, using many kinds of telescopes. Usually, these events are spotted by ground-based telescopes like the Zwicky Transient Facility and the All-Sky Automated Survey for Supernovae network.
They alert other ground- and space-based telescopes – like our Neil Gehrels Swift Observatory (illustrated above) and the European Space Agency’s XMM-Newton – to follow up and collect more data using different wavelengths, from visible light to X-rays. Even our planet-hunting Transiting Exoplanet Survey Satellite has observed a few of these destructive wonders!
We’re also studying disruptions using multimessenger astronomy, where scientists use the information carried by light, particles, and space-time ripples to learn more about cosmic objects and occurrences.
But tidal disruptions are super rare. They only happen once every 10,000 to 100,000 years in a galaxy the size of our own Milky Way. Astronomers have only observed a few dozen events so far. By comparison, supernovae – the explosive deaths of stars – happen every 100 years or so in a galaxy like ours.
That’s why scientists make their own tidal disruptions using supercomputers, like the ones shown in the video here. Supercomputers allow researchers to build realistic models of stars. They can also include all of the physical effects they’d experience whipping ‘round a black hole, even those from Einstein’s theory of general relativity. They can alter features like how close the stars get and how massive the black holes are to see how it affects what happens to the stars. These simulations will help astronomers build better pictures of the events they observe in the night sky.
Keep up with what’s happening in the universe and how we study it by following NASA Universe on Twitter and Facebook.
Make sure to follow us on Tumblr for your regular dose of space!
🏊♂️ Down for a dip in the Cosmic Reef?
Nicknamed the Cosmic Reef because it resembles an undersea world, this is a vast star-forming region in the Large Magellanic Cloud, a satellite galaxy of the Milky Way.
Released in April 2020 to celebrate the Hubble Space Telescope’s 30th anniversary, the reef showcases the beauty and mystery of space in this complex image of starbirth. Throughout its decades of discoveries, Hubble has yielded over 1.5 million observations, providing data that astronomers around the world have used to write more than 18,000 peer-reviewed scientific publications, making it the most prolific space observatory in history.
Learn more about Hubble’s celebration of Nebula November and see new nebula images, here.
You can also keep up with Hubble on Twitter, Instagram, Facebook, and Flickr!
Image credits: NASA, ESA, and STScI
These three towers are only a small portion of the massive Eagle Nebula.
Known as the “Pillars of Creation,” the beautiful tendrils of cosmic dust and gas are giving birth to new stars, buried within their spires. This iconic image only shows a stretch of about four or five light-years … while the whole nebula itself spans about 70 by 55 light-years.
Learn more about Hubble’s celebration of Nebula November and see new nebula images, here.
You can also keep up with Hubble on Twitter, Instagram, Facebook, and Flickr!
Image credits: NASA, ESA and the Hubble Heritage Team (STScI/AURA)
Spread your cosmic wings 🦋
The Butterfly Nebula, created by a dying star, was captured by the Hubble Space Telescope in this spectacular image. Observations were taken over a more complete spectrum of light, helping researchers better understand the “wings'' of gas bursting out from its center. The nebula’s dying central star has become exceptionally hot, shining ultraviolet light brightly over the butterfly’s wings and causing the gas to glow.
Learn more about Hubble’s celebration of Nebula November and see new nebula images, here.
You can also keep up with Hubble on Twitter, Instagram, Facebook, and Flickr!
Image credits: NASA, ESA, and J. Kastner (RIT)
The stunning Veil Nebula was created after a star about 20 times the mass of the Sun lived fast and died young – exploding in a cataclysmic release of energy known as a supernova.
In a violent stellar explosion roughly 10,000 years ago, shockwaves and debris created this staggeringly beautiful trail through space. The picture above shows a mosaic of six Hubble Space Telescope pictures, a small area roughly two light-years across, and only a tiny fraction of the nebula's vast 110 light-year structure.
To learn more about Hubble’s celebration of Nebula November and see new nebula images, visit our space telescope's nebula page.
You can also keep up with Hubble on Twitter, Instagram, Facebook, and Flickr!
Image credits: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
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.
Make sure to follow us on Tumblr for your regular dose of space!
The Roasted Planet
Can you hear this exoplanet screaming? As the exoplanet known as HD 80606 b approaches its star from an extreme, elliptical orbit, it suffers star-grazing torture that causes howling, supersonic winds and shockwave storms across this world beyond our solar system. Its torturous journey boils its atmosphere to a hellish 2,000 degrees Fahrenheit every 111 days, roasting both its light and dark sides. HD 80606b will never escape this scorching nightmare. Download this free poster in English and Spanish and check out the full Galaxy of Horrors.
Make sure to follow us on Tumblr for your regular dose of space!
Spotted: signs of a planet about 28 million light-years away 🔎 🪐
For the first time, astronomers may have detected an exoplanet candidate outside of the Milky Way galaxy. Exoplanets are defined as planets outside of our Solar System. All other known exoplanets and exoplanet candidates have been found in the Milky Way, almost all of them less than about 3,000 light-years from Earth.
This new result is based on transits, events in which the passage of a planet in front of a star blocks some of the star's light and produces a characteristic dip. Researchers used our Chandra X-ray Observatory to search for dips in the brightness of X-rays received from X-ray bright binaries in the spiral galaxy Messier 51, also called the Whirlpool Galaxy (pictured here). These luminous systems typically contain a neutron star or black hole pulling in gas from a closely orbiting companion star. They estimate the exoplanet candidate would be roughly the size of Saturn, and orbit the neutron star or black hole at about twice the distance of Saturn from the Sun.
This composite image of the Whirlpool Galaxy was made with X-ray data from Chandra and optical light from our Hubble Space Telescope.
Credit: X-ray: NASA/CXC/SAO/R. DiStefano, et al.; Optical: NASA/ESA/STScI/Grendler
Make sure to follow us on Tumblr for your regular dose of space!
The Exploration Behind the Inspiration at NASA
Are we alone? How did we get here? Where are we headed?
At NASA, our mission is to explore. We visit destinations in our solar system and study worlds beyond to better understand these big questions.
We also dream. We dream of traveling to distant worlds, and what that might be like. In the video above you can see fanciful, imagined adventures to real places we’ve studied at NASA.
How We Did It
Check out how we created these otherworldly scenes in the video below. A NASA videographer used green screens to add motion and real people to bring life to our series of solar system and exoplanet travel posters.
Let’s dive into one example from the video. The shot of kayaking on Titan showcases the real rivers and lakes of liquid methane and ethane that slosh and flow on Saturn's largest moon. Titan's mysterious surface was revealed by our Cassini spacecraft, which also deployed the European Space Agency’s Huygens probe to the surface. The atmosphere on Titan is so thick, and the gravity so light, that with each strike of a paddle, you might be lofted above the swift current as you ride the tides through a narrow strait called the Throat of Kraken. NASA scientist Mike Malaska studies Titan and collaborated on the poster featured in the video. His research informed the artwork, and so did a hobby: kayaking. Those ultra-cold chemical seas might be even more of a challenge than shown here. Your boat might crack, or even dissolve, Malaska said.
We’ll learn more about Titan when our Dragonfly mission of dual quadcoptors — rotorcraft with eight blades each — visits the icy moon in 2034.
Science Never Stops
Our understanding of other worlds is always evolving, and sometimes we learn new details after we illustrate our science. In one of our travel posters, we show a traveler standing on the surface of exoplanet Kepler-16b with two shadows formed by the planet’s two suns. The planet does indeed orbit two stars, but with later size and mass refinements, we now think it would be hard to stand there and enjoy a binary sunset. There isn't a solid surface to stand on a gas planet, and that's what Kepler-16b now appears to be!
In addition to sharing how sublime science can be, these scenes are a reminder that there are lots of careers in the space program, not just scientist, engineer, or astronaut. A creative team at NASA’s Jet Propulsion Laboratory in Southern California produced the travel posters, originally to help share the work of NASA's Exoplanet Exploration Program. They are the result of lots of brainstorming and discussion with real NASA scientists, engineers, and expert communicators. The video versions of these spacey travel scenes were produced by visualization experts at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
All of this work is meant to inspire, and to explore the edge of possibility. It’s also an invitation. With science, we’re stepping into the future. Join us?
Decoding Nebulae
We can agree that nebulae are some of the most majestic-looking objects in the universe. But what are they exactly? Nebulae are giant clouds of gas and dust in space. They’re commonly associated with two parts of the life cycle of stars: First, they can be nurseries forming new baby stars. Second, expanding clouds of gas and dust can mark where stars have died.
Not all nebulae are alike, and their different appearances tell us what's happening around them. Since not all nebulae emit light of their own, there are different ways that the clouds of gas and dust reveal themselves. Some nebulae scatter the light of stars hiding in or near them. These are called reflection nebulae and are a bit like seeing a street lamp illuminate the fog around it.
In another type, called emission nebulae, stars heat up the clouds of gas, whose chemicals respond by glowing in different colors. Think of it like a neon sign hanging in a shop window!
Finally there are nebulae with dust so thick that we’re unable to see the visible light from young stars shine through it. These are called dark nebulae.
Our missions help us see nebulae and identify the different elements that oftentimes light them up.
The Hubble Space Telescope is able to observe the cosmos in multiple wavelengths of light, ranging from ultraviolet, visible, and near-infrared. Hubble peered at the iconic Eagle Nebula in visible and infrared light, revealing these grand spires of dust and countless stars within and around them.
The Chandra X-ray Observatory studies the universe in X-ray light! The spacecraft is helping scientists see features within nebulae that might otherwise be hidden by gas and dust when viewed in longer wavelengths like visible and infrared light. In the Crab Nebula, Chandra sees high-energy X-rays from a pulsar (a type of rapidly spinning neutron star, which is the crushed, city-sized core of a star that exploded as a supernova).
The James Webb Space Telescope will primarily observe the infrared universe. With Webb, scientists will peer deep into clouds of dust and gas to study how stars and planetary systems form.
The Spitzer Space Telescope studied the cosmos for over 16 years before retiring in 2020. With the help of its detectors, Spitzer revealed unknown materials hiding in nebulae — like oddly-shaped molecules and soot-like materials, which were found in the California Nebula.
Studying nebulae helps scientists understand the life cycle of stars. Did you know our Sun got its start in a stellar nursery? Over 4.5 billion years ago, some gas and dust in a nebula clumped together due to gravity, and a baby Sun was born. The process to form a baby star itself can take a million years or more!
After billions more years, our Sun will eventually puff into a huge red giant star before leaving behind a beautiful planetary nebula (so-called because astronomers looking through early telescopes thought they resembled planets), along with a small, dense object called a white dwarf that will cool down very slowly. In fact, we don’t think the universe is old enough yet for any white dwarfs to have cooled down completely.
Since the Sun will live so much longer than us, scientists can't observe its whole life cycle directly ... but they can study tons of other stars and nebulae at different phases of their lives and draw conclusions about where our Sun came from and where it's headed. While studying nebulae, we’re seeing the past, present, and future of our Sun and trillions of others like it in the cosmos.
To keep up with the most recent cosmic news, follow NASA Universe on Twitter and Facebook.
Make sure to follow us on Tumblr for your regular dose of space.
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.
Make sure to follow us on Tumblr for your regular dose of space!
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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What’s Inside a ‘Dead’ Star?
Matter makes up all the stuff we can see in the universe, from pencils to people to planets. But there’s still a lot we don’t understand about it! For example: How does matter work when it’s about to become a black hole? We can’t learn anything about matter after it becomes a black hole, because it’s hidden behind the event horizon, the point of no return. So we turn to something we can study – the incredibly dense matter inside a neutron star, the leftover of an exploded massive star that wasn’t quite big enough to turn into a black hole.
Our Neutron star Interior Composition Explorer, or NICER, is an X-ray telescope perched on the International Space Station. NICER was designed to study and measure the sizes and masses of neutron stars to help us learn more about what might be going on in their mysterious cores.
When a star many times the mass of our Sun runs out of fuel, it collapses under its own weight and then bursts into a supernova. What’s left behind depends on the star’s initial mass. Heavier stars (around 25 times the Sun’s mass or more) leave behind black holes. Lighter ones (between about eight and 25 times the Sun’s mass) leave behind neutron stars.
Neutron stars pack more mass than the Sun into a sphere about as wide as New York City’s Manhattan Island is long. Just one teaspoon of neutron star matter would weigh as much as Mount Everest, the highest mountain on Earth!
These objects have a lot of cool physics going on. They can spin faster than blender blades, and they have powerful magnetic fields. In fact, neutron stars are the strongest magnets in the universe! The magnetic fields can rip particles off the star’s surface and then smack them down on another part of the star. The constant bombardment creates hot spots at the magnetic poles. When the star rotates, the hot spots swing in and out of our view like the beams of a lighthouse.
Neutron stars are so dense that they warp nearby space-time, like a bowling ball resting on a trampoline. The warping effect is so strong that it can redirect light from the star’s far side into our view. This has the odd effect of making the star look bigger than it really is!
NICER uses all the cool physics happening on and around neutron stars to learn more about what’s happening inside the star, where matter lingers on the threshold of becoming a black hole. (We should mention that NICER also studies black holes!)
Scientists think neutron stars are layered a bit like a golf ball. At the surface, there’s a really thin (just a couple centimeters high) atmosphere of hydrogen or helium. In the outer core, atoms have broken down into their building blocks – protons, neutrons, and electrons – and the immense pressure has squished most of the protons and electrons together to form a sea of mostly neutrons.
But what’s going on in the inner core? Physicists have lots of theories. In some traditional models, scientists suggested the stars were neutrons all the way down. Others proposed that neutrons break down into their own building blocks, called quarks. And then some suggest that those quarks could recombine to form new types of particles that aren’t neutrons!
NICER is helping us figure things out by measuring the sizes and masses of neutron stars. Scientists use those numbers to calculate the stars’ density, which tells us how squeezable matter is!
Let’s say you have what scientists think of as a typical neutron star, one weighing about 1.4 times the Sun’s mass. If you measure the size of the star, and it’s big, then that might mean it contains more whole neutrons. If instead it’s small, then that might mean the neutrons have broken down into quarks. The tinier pieces can be packed together more tightly.
NICER has now measured the sizes of two neutron stars, called PSR J0030+0451 and PSR J0740+6620, or J0030 and J0740 for short.
J0030 is about 1.4 times the Sun’s mass and 16 miles across. (It also taught us that neutron star hot spots might not always be where we thought.) J0740 is about 2.1 times the Sun’s mass and is also about 16 miles across. So J0740 has about 50% more mass than J0030 but is about the same size! Which tells us that the matter in neutron stars is less squeezable than some scientists predicted. (Remember, some physicists suggest that the added mass would crush all the neutrons and make a smaller star.) And J0740’s mass and size together challenge models where the star is neutrons all the way down.
So what’s in the heart of a neutron star? We’re still not sure. Scientists will have to use NICER’s observations to develop new models, perhaps where the cores of neutron stars contain a mix of both neutrons and weirder matter, like quarks. We’ll have to keep measuring neutron stars to learn more!
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Rare & Record-Breaking Black Holes
While even the most “normal” black hole seems exotic compared to the tranquil objects in our solar system, there are some record-breaking oddballs. Tag along as we look at the biggest, closest, farthest, and even “spinniest” black holes discovered in the universe … that we know of right now!
Located 700 million light-years away in the galaxy Holmberg 15A, astronomers found a black hole that is a whopping 40 billion times the mass of the Sun — setting the record for the biggest black hole found so far. On the other hand, the smallest known black hole isn’t quite so easy to pinpoint. There are several black holes with masses around five times that of our Sun. There’s even one candidate with just two and a half times the Sun’s mass, but scientists aren’t sure whether it’s the smallest known black hole or actually the heaviest known neutron star!
You may need to take a seat for this one. The black hole GRS 1915+105 will make you dizzier than an afternoon at an amusement park, as it spins over 1,000 times per second! Maybe even more bizarre than how fast this black hole is spinning is what it means for a black hole to spin at all! What we're actually measuring is how strongly the black hole drags the space-time right outside its event horizon — the point where nothing can escape. Yikes!
If you’re from Earth, the closest black hole that we know of right now, Mon X-1 in the constellation Monoceros, is about 3,000 light-years away. But never fear — that’s still really far away! The farthest known black hole is J0313-1806. The light from its surroundings took a whopping 13 billion years to get to us! And with the universe constantly expanding, that distance continues to grow.
So, we know about large (supermassive, hundreds of thousands to billions of times the Sun's mass) and small (stellar-mass, five to dozens of times the Sun's mass) black holes, but what about other sizes? Though rare, astronomers have found a couple that seem to fit in between and call them intermediate-mass black holes. As for tiny ones, primordial black holes, there is a possibility that they were around when the universe got its start — but there’s not enough evidence so far to prove that they exist!
One thing that’s on astronomers’ wishlist is to see two supermassive black holes crashing into one another. Unfortunately, that event hasn’t been detected — yet! It could be only a matter of time before one reveals itself.
Though these are the records now, in early 2021 … records are meant to be broken, so who knows what we’ll find next!
Add some of these records and rare finds to your black hole-watch list, grab your handy-dandy black hole field guide to learn even more about them — and get to searching!
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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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You’re Always Surrounded by Neutrinos!
This second, as you’re reading these words, trillions of tiny particles are hurtling toward you! No, you don’t need to brace yourself. They’re passing through you right now. And now. And now. These particles are called neutrinos, and they’re both everywhere in the cosmos and also extremely hard to find.
Neutrinos are fundamental particles, like electrons, so they can’t be broken down into smaller parts. They also outnumber all the atoms in the universe. (Atoms are made up of electrons, protons, and neutrons. Protons and neutrons are made of quarks … which maybe we’ll talk about another time.) The only thing that outnumbers neutrinos are all the light waves left over from the birth of the universe!
Credit: Photo courtesy of the Pauli Archive, CERN
Physicist Wolfgang Pauli proposed the existence of the neutrino, nearly a century ago. Enrico Fermi coined the name, which means “little neutral one” in Italian, because these particles have no electrical charge and nearly no mass.
Despite how many there are, neutrinos are really hard to study. They travel at almost the speed of light and rarely interact with other matter. Out of the universe’s four forces, ghostly neutrinos are only affected by gravity and the weak force. The weak force is about 10,000 times weaker than the electromagnetic force, which affects electrically charged particles. Because neutrinos carry no charge, move almost as fast as light, and don’t interact easily with other matter, they can escape some really bizarre and extreme places where even light might struggle getting out – like dying stars!
Through the weak force, neutrinos interact with other tiny fundamental particles: electrons, muons [mew-ons], and taus [rhymes with “ow”]. (These other particles are also really cool, but for right now, you just need to know that they’re there.) Scientists actually never detect neutrinos directly. Instead they find signals from these other particles. So they named the three types, or flavors, of neutrinos after them.
Neutrinos are made up of each of these three flavors, but cycle between them as they travel. Imagine going to the store to buy rocky road ice cream, which is made of chocolate ice cream, nuts, and marshmallows. When you get home, you find that it’s suddenly mostly marshmallows. Then in your bowl it’s mostly nuts. But when you take a bite, it’s just chocolate! That’s a little bit like what happens to neutrinos as they zoom through the cosmos.
Credit: CERN
On Earth, neutrinos are produced when unstable atoms decay, which happens in the planet’s core and nuclear reactors. (The first-ever neutrino detection happened in a nuclear reactor in 1955!) They’re also created by particle accelerators and high-speed particle collisions in the atmosphere. (Also, interestingly, the potassium in a banana emits neutrinos – but no worries, bananas are perfectly safe to eat!)
Most of the neutrinos around Earth come from the Sun – about 65 billion every second for every square centimeter. These are produced in the Sun’s core where the immense pressure squeezes together hydrogen to produce helium. This process, called nuclear fusion, creates the energy that makes the Sun shine, as well as neutrinos.
The first neutrinos scientists detected from outside the Milky Way were from SN 1987A, a supernova that occurred only 168,000 light-years away in a neighboring galaxy called the Large Magellanic Cloud. (That makes it one of the closest supernovae scientists have observed.) The light from this explosion reached us in 1987, so it was the first supernova modern astronomers were able to study in detail. The neutrinos actually arrived a few hours before the light from the explosion because of the forces we talked about earlier. The particles escape the star’s core before any of the other effects of the collapse ripple to the surface. Then they travel in pretty much a straight line – all because they don’t interact with other matter very much.
Credit: Martin Wolf, IceCube/NSF
How do we detect particles that are so tiny and fast – especially when they rarely interact with other matter? Well, the National Science Foundation decided to bury a bunch of detectors in a cubic kilometer of Antarctic ice to create the IceCube Neutrino Observatory. The neutrinos interact with other particles in the ice through the weak force and turn into muons, electrons, and taus. The new particles gain the neutrinos’ speed and actually travel faster than light in the ice, which produces a particular kind of radiation IceCube can detect. (Although they would still be slower than light in the vacuum of space.)
In 2013, IceCube first detected high-energy neutrinos, which have energies up to 1,000 times greater than those produced by Earth’s most powerful particle collider. But scientists were puzzled about where exactly these particles came from. Then, in 2017, IceCube detected a high-energy neutrino from a monster black hole powering a high-speed particle jet at a galaxy’s center billions of light-years away. It was accompanied by a flash of gamma rays, the highest energy form of light.
But particle jets aren’t the only place we can find these particles. Scientists recently announced that another high-energy neutrino came from a black hole shredding an unlucky star that strayed too close. The event didn’t produce the neutrino when or how scientists expected, though, so they’ve still got a lot to learn about these mysterious particles!
Keep up with other exciting announcements about our universe by following NASA Universe on Twitter and Facebook.
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An Addition to our Space Rock Collection
On October 20th, our OSIRIS-REx mission will make its first attempt to collect and retrieve a sample of asteroid Bennu, a near-Earth asteroid. On sample collection day, Bennu will be over 200 million miles away from Earth.
Asteroids are the building blocks of our solar system. A sample of this ancient material can tell us about the history of our planet and the origins of life. Science results published from the mission on October 8th confirm that Bennu contains carbon in a form often found in biology or in compounds associated with biology.
To collect a sample, OSIRIS-REx will attempt a method NASA has never used before – called Touch-And-Go (TAG). First, the spacecraft extends its robotic sampling arm, the Touch-And-Go Sample Acquisition Mechanism (TAGSAM) – from its folded storage position. The spacecraft’s two solar panels then move into a “Y-wing” configuration over the spacecraft’s body, which positions them safely up and away from the asteroid’s surface during touch down. This configuration also places the spacecraft’s center of gravity directly over the TAGSAM collector head, which is the only part of the spacecraft that will contact Bennu’s surface.
Finding a safe sample collection site on Bennu’s rocky landscape was a challenge. During the sampling event, the spacecraft, which is the size of a large van, will attempt to touch down in an area that is only the size of a few parking spaces, and just a few steps away from enormous boulders.
The spacecraft will only make contact with Bennu for a matter of seconds - just long enough to blow nitrogen gas onto the surface to roil up dust and small pebbles, which will then be captured for a return to Earth.
We need to conduct a few tests before we can confirm we collected a large enough sample (about 2 oz). First, OSIRIS-REx will take images of the collector head to see if it contains rocks and dust. Second, the spacecraft will spin with the TAGSAM extended to determine the mass of collected material. If these measures show a successful collection, we will stow the sample for return to Earth. If sufficient sample has not been collected, the spacecraft has onboard nitrogen charges for two more attempts. The next TAG attempt would be made no earlier than January 2021.
Despite the many challenges, the OSIRIS-REx team is ready. They’ve practiced and prepared for this moment.
Join in with #ToBennuAndBack and tune in on October 20th.
Learn more about the OSIRIS-REx countdown to TAG HERE.
Learn more about the OSIRIS-REx mission HERE, or follow the mission on Facebook, Twitter and Instagram.
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10 Ways the Webb Telescope ‘Trains’ for Space
The James Webb Space Telescope will peer at the first stars and galaxies as a cosmic time machine, look beyond to distant worlds, and unlock the mysteries of the universe. But before it can do any of those things, it needs to “train” for traveling to its destination — 1 million miles away from Earth!
So how does Webb get ready for space while it’s still on the ground? Practice makes perfect. Different components of the telescope were first tested on their own, but now a fully-assembled Webb is putting all of its training together. Here are 10 types of tests that Webb went through to prepare for its epic journey:
1. Sounding Off
A rocket launch is 100 times more intense and four times louder than a rock concert! (That’s according to Paul Geithner, Webb’s deputy project manager – technical.) To simulate that level of extreme noise, Webb’s full structure was blasted with powerful sound waves during its observatory-level acoustic testing in August.
2. Shaking It Up
Webb will also have to withstand a super-bumpy ride as it launches — like a plane takeoff, but with a lot more shaking! The observatory was carefully folded into its launch position, placed onto a shaker table, and vibrated from 5 to 100 times per second to match the speeds of Webb’s launch vehicle, an Ariane 5 rocket.
3. All Systems Go
In July, Webb performed a rigorous test of its software and electrical systems as a fully connected telescope. Each line of code for Webb was tested and then retested as different lines were combined into Webb’s larger software components. To complete this test, Webb team members were staffed 24 hours a day for 15 consecutive days!
4. Hanging Out
After launch, Webb is designed to unfold (like origami in reverse) from its folded launch position into its operational form. Without recharging, the telescope’s onboard battery would only last a few hours, so it will be up to Webb’s 20-foot solar array to harness the Sun’s energy for all of the telescope’s electrical needs. To mimic the zero-gravity conditions of space, Webb technicians tested the solar array by hanging it sideways.
5. Time to Stretch
The tower connects the upper and lower halves of Webb. Once Webb is in space, the tower will extend 48 inches (1.2 meters) upward to create a gap between the two halves of the telescope. Then all five layers of Webb’s sunshield will slowly unfurl and stretch out, forming what will look like a giant kite in space. Both the tower and sunshield will help different sections of Webb maintain their ideal temperatures.
For these steps, engineers designed an ingenious system of cables, pulleys and weights to counter the effects of Earth’s gravity. 6. Dance of the Mirrors
Unfolding Webb’s mirrors will involve some dance-like choreography. First, a support structure will gracefully unfold to place the circular secondary mirror out in front of the primary mirror. Although small, the secondary mirror will play a big role: focusing light from the primary mirror to send to Webb’s scientific instruments.
Next, Webb’s iconic primary mirror will fully extend so that all 18 hexagonal segments are in view. At 6.5 meters (21 feet 4-inches) across, the mirror’s massive size is key for seeing in sharp detail. Like in tower and sunshield testing, the Webb team offloaded the weight of both mirrors with cables, pulleys and weights so that they unfolded as if weightless in space.
7. Do Not Disturb
Before a plane takeoff, it’s important for us to turn off our cell phones to make sure that their electromagnetic waves won’t interfere with navigation signals. Similarly, Webb had to test that its scientific instruments wouldn’t disrupt the electromagnetic environment of the spacecraft. This way, when we get images back from Webb, we’ll know that we’re seeing actual objects in space instead of possible blips caused by electromagnetic interference. These tests took place in the Electromagnetic Interference (EMI) Lab, which looks like a futuristic sound booth! Instead of absorbing sound, however, the walls of this chamber help keep electromagnetic waves from bouncing around.
8. Phoning Earth
How will Webb know where to go and what to look at? Thanks to Webb’s Ground Segment Tests, we know that we’ll be able to “talk” to Webb after liftoff. In the first six hours after launch, the telescope needs to seamlessly switch between different communication networks and stations located around the world. Flight controllers ran through these complex procedures in fall 2018 to help ensure that launch will be a smooth success.
After Webb reaches its destination, operators will use the Deep Space Network, an international array of giant radio antennas, to relay commands that tell Webb where to look. To test this process when Webb isn’t in space yet, the team used special equipment to imitate the real radio link that will exist between the observatory and the network.
9. Hot and Cold
Between 2017 and 2019, Webb engineers separately tested the two halves of the telescope in different thermal vacuum chambers, which are huge, climate-controlled rooms drained of air to match the vacuum of space. In testing, the spacecraft bus and sunshield half were exposed to both boiling hot and freezing cold temperatures, like the conditions that they’ll encounter during Webb’s journey.
But Webb’s mirrors and instruments will need to be colder than cold to operate! This other half of Webb was tested in the historic Chamber A, which was used to test Apollo Moon mission hardware and specifically upgraded to fit Webb. Over about 100 days, Chamber A was gradually cooled down, held at cryogenic temperatures (about minus 387 F, or minus 232.8 C), and then warmed back up to room temperature.
10. Cosmic Vision
When the Hubble Space Telescope was first sent into space, its images were blurry due to a flaw with its mirror. This error taught us about the importance of comprehensively checking Webb’s “eyes” before the telescope gets out of reach.
Besides training for space survival, Webb also spent time in Chamber A undergoing mirror alignment and optical testing. The team used a piece of test hardware that acted as a source of artificial starlight to verify that light would travel correctly through Webb’s optical system.
Whew! That’s a lot of testing under Webb’s belt! Webb is set to launch in October 2021 from Kourou, French Guiana. But until then, it’s still got plenty of training left, including a final round of deployment tests before being shipped to its launch location.
Learn more about the James Webb Space Telescope HERE, or follow the mission on Facebook, Twitter and Instagram.
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Bend Your Mind With Special Relativity
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!
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.
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!
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!
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.
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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10 Amazing Space Discoveries by the World’s Largest Flying Observatory
On the night of May 26, 2010, the Stratospheric Observatory for Infrared Astronomy, or SOFIA, the world’s largest flying observatory, first peered into the cosmos. Its mission: to study celestial objects and astronomical phenomena with infrared light. Many objects in space emit almost all their energy at infrared wavelengths. Often, they are invisible when observed in ordinary, visible light. Over the last decade, the aircraft’s 106-inch telescope has been used to study black holes, planets, galaxies, star-forming nebulas and more! The observations have led to major breakthroughs in astronomy, revolutionizing our understanding of the solar system and beyond. To celebrate its 10 years of exploration, here’s a look at the top 10 discoveries made by our telescope on a plane:
The Universe’s First Type of Molecule
Scientists believe that around 100,000 years after the big bang, helium and hydrogen combined to make a molecule called helium hydride. Its recent discovery confirms a key part of our basic understanding of the early universe.
A New View of the Milky Way
More than a pretty picture, this panorama of cosmic scale reveals details that can help explain how massive stars are born and what’s feeding our Milky Way galaxy's supermassive black hole.
When Planets Collide
A double-star system that is more than 300 light-years away likely had an extreme collision between two of its rocky planets. A similar event in our own solar system may have formed our Moon.
How A Black Hole Feasts
Fear not, the dark, my friend. And let the feast begin! Magnetic fields in the Cygnus A galaxy are trapping material where it is close enough to be devoured by a hungry black hole.
Somewhere Like Home
The planetary system around Epsilon Eridani, a star located about 10 light-years away, has an architecture remarkably similar to our solar system. What’s more, its central star is a younger, fainter version of our Sun.
A Quiet Place
Black holes in many galaxies are actively consuming material, but our Milky Way galaxy’s central black hole is relatively quiet. Observations show magnetic fields may be directing material around, not into, the belly of the beast.
The Great Escape
Ever wonder how material leaves a galaxy? The wind flowing from the center of the Cigar Galaxy is so strong it's pulling a magnetic field — and the mass of 50 to 60 million Suns — with it.
Exploding Star, New Worlds
What happens when a star goes boom? It turns out that supernova explosions can produce a substantial amount of material from which planets like Earth can form.
Stellar Sibling Rivalry
They say siblings need time and space to grow, but here’s one that really needs some room. A newborn star in the Orion Nebula is clearing a bubble of space around it, preventing any new luminous family members from forming nearby.
Clues to Life’s Building Blocks
Radiation from stars is making organic molecules in nebula NGC 7023, also known as the Iris Nebula, larger and more complex. The growth of these molecules is one of the steps that could lead to the emergence of life under the right circumstances.
SOFIA is a modified Boeing 747SP aircraft that allows astronomers to study the solar system and beyond in ways that are not possible with ground-based telescopes. Find out more about the mission at www.nasa.gov/SOFIA.
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