Category: telescope

Ten Observations From Our Flying Telescope

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SOFIA is a Boeing 747SP aircraft with a 100-inch telescope used to study the solar system and beyond by observing infrared light that can’t reach Earth’s surface.

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What is infrared light? It’s light we cannot see with our eyes that is just beyond the red portion of visible light we see in a rainbow. It can be used to change your TV channels, which is how remote controls work, and it can tell us how hot things are.

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Everything emits infrared radiation, even really cold objects like ice and newly forming stars! We use infrared light to study the life cycle of stars, the area around black holes, and to analyze the chemical fingerprints of complex molecules in space and in the atmospheres of other planets – including Pluto and Mars.

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Above, is the highest-resolution image of the ring of dust and clouds around the back hole at the center of our Milky Way Galaxy. The bright Y-shaped feature is believed to be material falling from the ring into the black hole – which is located where the arms of the Y intersect.

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The magnetic field in the galaxy M82 (pictured above) aligns with the dramatic flow of material driven by a burst of star formation. This is helping us learn how star formation shapes magnetic fields of an entire galaxy.

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A nearby planetary system around the star Epsilon Eridani, the location of the fictional Babylon 5 space station, is similar to our own: it’s the closest known planetary system around a star like our sun and it also has an asteroid belt adjacent to the orbit of its largest, Jupiter-sized planet.

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Observations of a supernova that exploded 10,000 years ago, that revealed it contains enough dust to make 7,000 Earth-sized planets!

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Measurements of Pluto’s upper atmosphere, made just two weeks before our New Horizons spacecraft’s Pluto flyby. Combining these observations with those from the spacecraft are helping us understand the dwarf planet’s atmosphere.

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A gluttonous star that has eaten the equivalent of 18 Jupiters in the last 80 years, which may change the theory of how stars and planets form.

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Molecules like those in your burnt breakfast toast may offer clues to the building blocks of life. Scientists hypothesize that the growth of complex organic molecules like these is one of the steps leading to the emergence of life.

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This map of carbon molecules in Orion’s Horsehead nebula (overlaid on an image of the nebula from the Palomar Sky Survey) is helping us understand how the earliest generations of stars formed. Our instruments on SOFIA use 14 detectors simultaneously, letting us make this map faster than ever before!

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Pinpointing the location of water vapor in a newly forming star with groundbreaking precision. This is expanding our understanding of the distribution of water in the universe and its eventual incorporation into planets. The water vapor data from SOFIA is shown above laid over an image from the Gemini Observatory.

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We captured the chemical fingerprints that revealed celestial clouds collapsing to form young stars like our sun. It’s very rare to directly observe this collapse in motion because it happens so quickly. One of the places where the collapse was observed is shown in this image from The Two Micron All Sky Survey.

Learn more by following SOFIA on Facebook, Twitter and Instagram.

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What’s Made in a Thunderstorm and Faster Than …

A flash of lightning. A roll of thunder. These are normal stormy sights and sounds. But sometimes, up above the clouds, stranger things happen. Our Fermi Gamma-ray Space Telescope has spotted bursts of gamma rays – some of the highest-energy forms of light in the universe – coming from thunderstorms. Gamma rays are usually found coming from objects with crazy extreme physics like neutron stars and black holes

So why is Fermi seeing them come from thunderstorms?

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Thunderstorms form when warm, damp air near the ground starts to rise and encounters colder air. As the warm air rises, moisture condenses into water droplets. The upward-moving water droplets bump into downward-moving ice crystals, stripping off electrons and creating a static charge in the cloud.

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The top of the storm becomes positively charged, and the bottom becomes negatively charged, like two ends of a battery. Eventually the opposite charges build enough to overcome the insulating properties of the surrounding air – and zap! You get lightning.

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Scientists suspect that lightning reconfigures the cloud’s electrical field. In some cases this allows electrons to rush toward the upper part of the storm at nearly the speed of light. That makes thunderstorms the most powerful natural particle accelerators on Earth!

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When those electrons run into air molecules, they emit a terrestrial gamma-ray flash, which means that thunderstorms are creating some of the highest energy forms of light in the universe. But that’s not all – thunderstorms can also produce antimatter! Yep, you read that correctly! Sometimes, a gamma ray will run into an atom and produce an electron and a positron, which is an electron’s antimatter opposite!

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The Fermi Gamma-ray Space Telescope can spot terrestrial gamma-ray flashes within 500 miles of the location directly below the spacecraft. It does this using an instrument called the Gamma-ray Burst Monitor which is primarily used to watch for spectacular flashes of gamma rays coming from the universe.

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There are an estimated 1,800 thunderstorms occurring on Earth at any given moment. Over the 10 years that Fermi has been in space, it has spotted about 5,000 terrestrial gamma-ray flashes. But scientists estimate that there are 1,000 of these flashes every day – we’re just seeing the ones that are within 500 miles of Fermi’s regular orbits, which don’t cover the U.S. or Europe.

The map above shows all the flashes Fermi has seen since 2008. (Notice there’s a blob missing over the lower part of South America. That’s the South Atlantic Anomaly, a portion of the sky where radiation affects spacecraft and causes data glitches.)

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Fermi has also spotted terrestrial gamma-ray flashes coming from individual tropical weather systems. The most productive system we’ve seen was Tropical Storm Julio in 2014, which later became a hurricane. It produced four flashes in just 100 minutes!

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Learn more about what Fermi’s discovered about gamma rays over the last 10 years and how we’re celebrating its accomplishments.

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Solar System: 10 Things to Know This Week

Planets Outside Our Solar System

Let the planet-hunting begin!

Our Transiting Exoplanet Survey Satellite (TESS), which will scan the skies to look for planets beyond our solar system—known as exoplanets—is now in Florida to begin preparations for launch in April. Below, 10 Things to know about the many, many unknown planets out there awaiting our discovery.

1Exo-what?

We call planets in our solar system, well, planets, but the many planets we’re starting to discover outside of our solar system are called exoplanets. Basically, they’re planets that orbit another star.

2All eyes on TRAPPIST-1.

Remember the major 2016 announcement that we had discovered seven planets 40 light-years away, orbiting a star called TRAPPIST-1? Those are all exoplanets. (Here’s a refresher.)

3Add 95 new ones to that.

Just last month, our Kepler telescope discovered 95 new exoplanets beyond our solar system (on top of the thousands of exoplanets Kepler has discovered so far). The total known planet count beyond our solar system is now more than 3,700. The planets range in size from mostly rocky super-Earths and fluffy mini-Neptunes, to Jupiter-like giants. They include a new planet orbiting a very bright star—the brightest star ever discovered by Kepler to have a transiting planet.

4Here comes TESS.

How many more exoplanets are out there waiting to be discovered? TESS will monitor more than 200,000 of the nearest and brightest stars in search of transit events—periodic dips in a star’s brightness caused by planets passing in front—and is expected to find thousands of exoplanets.

5With a sidekick, too.

Our upcoming James Webb Space Telescope, will provide important follow-up observations of some of the most promising TESS-discovered exoplanets. It will also allow scientists to study their atmospheres and, in some special cases, search for signs that these planets could support life.

6Prepped for launch.

TESS is scheduled to launch on a SpaceX Falcon 9 rocket from Cape Canaveral Air Force Station nearby our Kennedy Space Center in Florida, no earlier than April 16, pending range approval.

7A groundbreaking find.

In 1995, 51 Pegasi b (also called “Dimidium”) was the first exoplanet discovered orbiting a star like our Sun. This find confirmed that planets like the ones in our solar system could exist elsewhere in the universe.

8Trillions await.

A recent statistical estimate places, on average, at least one planet around every star in the galaxy. That means there could be a trillion planets in our galaxy alone, many of them in the range of Earth’s size.

9Signs of life.

Of course, our ultimate science goal is to find unmistakable signs of current life. How soon can that happen? It depends on two unknowns: the prevalence of life in the galaxy and a bit of luck. Read more about the search for life.

10Want to explore the galaxy?

No need to be an astronaut. Take a trip outside our solar system with help from our Exoplanet Travel Bureau.

Read the full version of this week’s ‘10 Things to Know’ article HERE

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What’s Inside SOFIA? High Flying Instruments

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Our flying observatory, called SOFIA, carries a 100-inch telescope inside a Boeing 747SP aircraft. Having an airborne observatory provides many benefits.

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It flies at 38,000-45,000 feet – above 99% of the water vapor in Earth’s atmosphere that blocks infrared light from reaching the ground! 

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It is also mobile! We can fly to the best vantage point for viewing the cosmos. We go to Christchurch, New Zealand, nearly every year to study objects best observed from the Southern Hemisphere. And last year we went to Daytona Beach, FL, to study the atmosphere of Neptune’s moon Triton while flying over the Atlantic Ocean.

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SOFIA’s telescope has a large primary mirror – about the same size as the Hubble Space Telescope’s mirror. Large telescopes let us gather a lot of light to make high-resolution images!

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But unlike a space-based observatory, SOFIA returns to our base every morning.

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Which means that we can change the instruments we use to analyze the light from the telescope to make many different types of scientific observations. We currently have seven instruments, and new ones are now being developed to incorporate new technologies.

So what is inside SOFIA? The existing instruments include:

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Infrared cameras that can peer inside celestial clouds of dust and gas to see stars forming inside. They can also study molecules in a nebula that may offer clues to the building blocks of life

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…A polarimeter, a device that measures the alignment of incoming light waves, that we use to study magnetic fields. The left image reveals that hot dust in the starburst galaxy M82 is magnetically aligned with the gas flowing out of it, shown in blue on the right image from our Chandra X-ray Observatory. This can help us understand how magnetic fields affect how stars form.

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…A tracking camera that we used to study New Horizon’s post-Pluto flyby target and found that it may have its own moon

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…A spectrograph that spreads light into its component colors. We’re using one to search for signs of water plumes on Jupiter’s icy moon Europa and to search for signs of water on Venus to learn about how it lost its oceans

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…An instrument that studies high energy terahertz radiation with 14 detectors. It’s so efficient that we made this map of Orion’s Horsehead Nebula in only four hours! The map is made of 100 separate views of the nebula, each mapping carbon atoms at different velocities.

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…And we have an instrument under construction that will soon let us study how water vapor, ice and oxygen combine at different times during planet formation, to better understand how these elements combine with dust to form a mass that can become a planet.

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Our airborne telescope has already revealed so much about the universe around us! Now we’re looking for the next idea to help us use SOFIA in even more new ways. 

Discover more about our SOFIA flying observatory HERE

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The Universe’s Brightest Lights Have Some Dark…

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

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

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

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

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

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

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

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

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

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When galaxies collide — a common event in the …

When galaxies collide — a common event in the
universe — a fresh burst of star formation typically takes place as gas clouds
mash together. At this point, the galaxy has a blue hue, but the color does not
mean it is cold: it is a result of the intense heat of newly formed blue–white
stars. Those stars do not last long, and after a few billion years the reddish
hues of aging, smaller stars dominate an elliptical galaxy’s spectrum. 

Our Hubble Space Telescope (@NASAHubble) caught
sight of a soft, diffuse-looking galaxy, perhaps the aftermath of a long-ago
galactic collision when two spiral galaxies, each perhaps much like the Milky
Way, swirled together for millions of years.

In such mergers, the original galaxies are often
stretched and pulled apart as they wrap around a common center of gravity.
After a few back-and-forths, this starry tempest settles down into a new, round
object. The now subdued celestial body is technically known as an elliptical
galaxy.

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Credit: ESA/Hubble & NASA

Infrared is Beautiful

Why was James Webb Space Telescope designed to observe infrared light? How can its images hope to compare to those taken by the (primarily) visible-light Hubble Space Telescope? The short answer is that Webb will absolutely capture beautiful images of the universe, even if it won’t see exactly what Hubble sees. (Spoiler: It will see a lot of things even better.)

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The James Webb Space Telescope, or Webb, is our upcoming infrared space observatory, which will launch in 2019. It will spy the first luminous objects that formed in the universe and shed light on how galaxies evolve, how stars and planetary systems are born, and how life could form on other planets.

What is infrared light? 

This may surprise you, but your remote control uses light waves just beyond the visible spectrum of light—infrared light waves—to change channels on your TV.

Infrared light shows us how hot things are. It can also show us how cold things are. But it all has to do with heat. Since the primary source of infrared radiation is heat or thermal radiation, any object that has a temperature radiates in the infrared. Even objects that we think of as being very cold, such as an ice cube, emit infrared.

There are legitimate scientific reasons for Webb to be an infrared telescope. There are things we want to know more about, and we need an infrared telescope to learn about them. Things like: stars and planets being born inside clouds of dust and gas; the very first stars and galaxies, which are so far away the light they emit has been stretched into the infrared; and the chemical fingerprints of elements and molecules in the atmospheres of exoplanets, some of which are only seen in the infrared.

In a star-forming region of space called the ‘Pillars of Creation,’ this is what we see with visible light:

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And this is what we see with infrared light:

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Infrared light can pierce through obscuring dust and gas and unveil a more unfamiliar view.

Webb will see some visible light: red and orange. But the truth is that even though Webb sees mostly infrared light, it will still take beautiful images. The beauty and quality of an astronomical image depends on two things: the sharpness of the image and the number of pixels in the camera. On both of these counts, Webb is very similar to, and in many ways better than, Hubble. Webb will take much sharper images than Hubble at infrared wavelengths, and Hubble has comparable resolution at the visible wavelengths that Webb can see.

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Webb’s infrared data can be translated by computer into something our eyes can appreciate – in fact, this is what we do with Hubble data. The gorgeous images we see from Hubble don’t pop out of the telescope looking fully formed. To maximize the resolution of the images, Hubble takes multiple exposures through different color filters on its cameras.

The separate exposures, which look black and white, are assembled into a true color picture via image processing. Full color is important to image analysis of celestial objects. It can be used to highlight the glow of various elements in a nebula, or different stellar populations in a galaxy. It can also highlight interesting features of the object that might be overlooked in a black and white exposure, and so the images not only look beautiful but also contain a lot of useful scientific information about the structure, temperatures, and chemical makeup of a celestial object.

This image shows the sequences in the production of a Hubble image of nebula Messier 17:

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Here’s another compelling argument for having telescopes that view the universe outside the spectrum of visible light – not everything in the universe emits visible light. There are many phenomena which can only be seen at certain wavelengths of light, for example, in the X-ray part of the spectrum, or in the ultraviolet. When we combine images taken at different wavelengths of light, we can get a better understanding of an object, because each wavelength can show us a different feature or facet of it. 

Just like infrared data can be made into something meaningful to human eyes, so can each of the other wavelengths of light, even X-rays and gamma-rays.

Below is an image of the M82 galaxy created using X-ray data from the Chandra X-ray Observatory, infrared data from the Spitzer Space Telescope, and visible light data from Hubble. Also note how aesthetically pleasing the image is despite it not being just optical light:

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Though Hubble sees primarily visible light, it can see some infrared. And despite not being optimized for it, and being much less powerful than Webb, it still produced this stunning image of the Horsehead Nebula.

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It’s a big universe out there – more than our eyes can see. But with all the telescopes now at our disposal (as well as the new ones that will be coming online in the future), we are slowly building a more accurate picture. And it’s definitely a beautiful one. Just take a look…

…At this Spitzer infrared image of a shock wave in dust around the star Zeta Ophiuchi.

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…this Spitzer image of the Helix Nebula, created using infrared data from the telescope and ultraviolet data from the Galaxy Evolution Explorer.

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…this image of the “wing” of the Small Magellanic Cloud, created with infrared data from Spitzer and X-ray data from Chandra.

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…the below image of the Milky Way’s galactic center, taken with our flying SOFIA telescope. It flies at more than 40,000 feet, putting it above 99% of the  water vapor in Earth’s atmosphere– critical for observing infrared because water vapor blocks infrared light from reaching the ground. This infrared view reveals the ring of gas and dust around a supermassive black hole that can’t be seen with visible light. 

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…and this Hubble image of the Mystic Mountains in the Carina Nebula.

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

Image Credits
Eagle Nebula: NASA, ESA/Hubble and the Hubble Heritage Team
Hubble Image Processing – Messier 17: NASA/STScI
Galaxy M82 Composite Image: NASA, CXC, JHU, D.Strickland, JPL-Caltech, C. Engelbracht (University of Arizona), ESA, and The Hubble Heritage Team (STScI/AURA)
Horsehead Nebula: NASA, ESA, and The Hubble Heritage Team (STScI/AURA)
Zeta Ophiuchi: NASA/JPL-Caltech
Helix Nebula: NASA/JPL-Caltech
Wing of the Small Magellanic Cloud
X-ray: NASA/CXC/Univ.Potsdam/L.Oskinova et al; Optical: NASA/STScI; Infrared: NASA/JPL-Caltech
Milky Way Circumnuclear Ring: NASA/DLR/USRA/DSI/FORCAST Team/ Lau et al. 2013
Mystic Mountains in the Carina Nebula: NASA/ESA/M. Livio & Hubble 20th Anniversary Team (STScI)

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The Beauty of Webb Telescope’s Mirrors

The James Webb Space Telescope’s gold-plated, beryllium mirrors are beautiful feats of engineering. From the 18 hexagonal primary mirror segments, to the perfectly circular secondary mirror, and even the slightly trapezoidal tertiary mirror and the intricate fine-steering mirror, each reflector went through a rigorous refinement process before it was ready to mount on the telescope. This flawless formation process was critical for Webb, which will use the mirrors to peer far back in time to capture the light from the first stars and galaxies. 

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The James Webb Space Telescope, or Webb, is our upcoming infrared space observatory, which will launch in 2019. It will spy the first luminous objects that formed in the universe and shed light on how galaxies evolve, how stars and planetary systems are born, and how life could form on other planets.  

A polish and shine that would make your car jealous

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All of the Webb telescope’s mirrors were polished to accuracies of approximately one millionth of an inch. The beryllium mirrors were polished at room temperature with slight imperfections, so as they change shape ever so slightly while cooling to their operating temperatures in space, they achieve their perfect shape for operations.

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The Midas touch

Engineers used a process called vacuum vapor deposition to coat Webb’s mirrors with an ultra-thin layer of gold. Each mirror only required about 3 grams (about 0.11 ounces) of gold. It only took about a golf ball-sized amount of gold to paint the entire main mirror!

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Before the deposition process began, engineers had to be absolutely sure the mirror surfaces were free from contaminants. 

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The engineers thoroughly wiped down each mirror, then checked it in low light conditions to ensure there was no residue on the surface.

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Inside the vacuum deposition chamber, the tiny amount of gold is turned into a vapor and deposited to cover the entire surface of each mirror.

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Primary, secondary, and tertiary mirrors, oh my!

Each of Webb’s primary mirror segments is hexagonally shaped. The entire 6.5-meter (21.3-foot) primary mirror is slightly curved (concave), so each approximately 1.3-meter (4.3-foot) piece has a slight curve to it.

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Those curves repeat themselves among the segments, so there are only three different shapes — 6 of each type. In the image below, those different shapes are labeled as A, B, and C.

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Webb’s perfectly circular secondary mirror captures light from the 18 primary mirror segments and relays those images to the telescope’s tertiary mirror.

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The secondary mirror is convex, so the reflective surface bulges toward a light source. It looks much like a curved mirror that you see on the wall near the exit of a parking garage that lets motorists see around a corner.

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Webb’s trapezoidal tertiary mirror captures light from the secondary mirror and relays it to the fine-steering mirror and science instruments. The tertiary mirror sits at the center of the telescope’s primary mirror. The tertiary mirror is the only fixed mirror in the system — all of the other mirrors align to it.

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All of the mirrors working together will provide Webb with the most advanced infrared vision of any space observatory we’ve ever launched!

Who is the fairest of them all?

The beauty of Webb’s primary mirror was apparent as it rotated past a cleanroom observation window at our Goddard Space Flight Center in Greenbelt, Maryland. If you look closely in the reflection, you will see none other than James Webb Space Telescope senior project scientist and Nobel Laureate John Mather!

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

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Meet Fermi: Our Eyes on the Gamma-Ray Sky

Black holes, cosmic rays, neutron stars and even new kinds of physics — for 10 years, data from our Fermi Gamma-ray Space Telescope have helped unravel some of the biggest mysteries of the cosmos. And Fermi is far from finished!

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On June 11, 2008, at Cape Canaveral in Florida, the countdown started for Fermi, which was called the Gamma-ray Large Area Space Telescope (GLAST) at the time. 

The telescope was renamed after launch to honor Enrico Fermi, an Italian-American pioneer in high-energy physics who also helped develop the first nuclear reactor. 

Fermi has had many other things named after him, like Fermi’s Paradox, the Fermi National Accelerator Laboratory, the Enrico Fermi Nuclear Generating Station, the Enrico Fermi Institute, and the synthetic element fermium.

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Photo courtesy of Argonne National Laboratory

The Fermi telescope measures some of the highest energy bursts of light in the universe; watching the sky to help scientists answer all sorts of questions about some of the most powerful objects in the universe. 

Its main instrument is the Large Area Telescope (LAT), which can view 20% of the sky at a time and makes a new image of the whole gamma-ray sky every three hours. Fermi’s other instrument is the Gamma-ray Burst Monitor. It sees even more of the sky at lower energies and is designed to detect brief flashes of gamma-rays from the cosmos and Earth.

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This sky map below is from 2013 and shows all of the high energy gamma rays observed by the LAT during Fermi’s first five years in space.  The bright glowing band along the map’s center is our own Milky Way galaxy!

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So what are gamma rays? 

Well, they’re a form of light. But light with so much energy and with such short wavelengths that we can’t see them with the naked eye. Gamma rays require a ton of energy to produce — from things like subatomic particles (such as protons) smashing into each other. 

Here on Earth, you can get them in nuclear reactors and lightning strikes. Here’s a glimpse of the Seattle skyline if you could pop on a pair of gamma-ray goggles. That purple streak? That’s still the Milky Way, which is consistently the brightest source of gamma rays in our sky.

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In space, you find that kind of energy in places like black holes and neutron stars. The raindrop-looking animation below shows a big flare of gamma rays that Fermi spotted coming from something called a blazar, which is a kind of quasar, which is different from a pulsar… actually, let’s back this up a little bit.

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One of the sources of gamma rays that Fermi spots are pulsars. Pulsars are a kind of neutron star, which is a kind of star that used to be a lot bigger, but collapsed into something that’s smaller and a lot denser. Pulsars send out beams of gamma rays. But the thing about pulsars is that they rotate. 

So Fermi only sees a beam of gamma rays from a pulsar when it’s pointed towards Earth. Kind of like how you only periodically see the beam from a lighthouse. These flashes of light are very regular. You could almost set your watch by them!

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Quasars are supermassive black holes surrounded by disks of gas. As the gas falls into the black hole, it releases massive amount of energy, including — you guessed it — gamma rays. Blazars are quasars that send out beams of gamma rays and other forms of light — right in our direction. 

When Fermi sees them, it’s basically looking straight down this tunnel of light, almost all the way back to the black hole. This means we can learn about the kinds of conditions in that environment when the rays were emitted. Fermi has found about 5,500 individual sources of gamma rays, and the bulk of them have been blazars, which is pretty nifty.

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But gamma rays also have many other sources. We’ve seen them coming from supernovas where stars die and from star factories where stars are born. They’re created in lightning storms here on Earth, and our own Sun can toss them out in solar flares. 

Gamma rays were in the news last year because of something Fermi spotted at almost the same time as the National Science Foundation (NSF)’s Laser Interferometer Gravitational-Wave Observatory (LIGO) and European Gravitational Observatory’s Virgo on August 17, 2017. Fermi, LIGO, Virgo, and numerous other observatories spotted the merger of two neutron stars. It was the first time that gravitational waves and light were confirmed to come from the same source.

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Fermi has been looking at the sky for almost 10 years now, and it’s helped scientists advance our understanding of the universe in many ways. And the longer it looks, the more we’ll learn. Discover more about how we’ll be celebrating Fermi’s achievements all year.

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Researchers Just Found (For The First Time) An…

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Our Milky Way galaxy is full of hundreds of billions of
worlds just waiting to be found. In 2014, scientists using data from our planet-hunting
Kepler space telescope discovered seven planets orbiting Kepler-90, a Sun-like star
located 2,500 light-years away. Now, an eighth planet has been identified in this
planetary system, making it tied with our own solar system in having the highest
number of known planets. Here’s what you need to know:

The new planet is called Kepler-90i.

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Kepler-90i is a sizzling hot, rocky planet. It’s the smallest of eight planets in the Kepler-90 system. It orbits so close to its star that a “year” passes in just 14 days.

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Average surface temperatures on Kepler-90i are estimated to hover around 800 degrees Fahrenheit, making it an unlikely place for life as we know it.

Its planetary system is like a scrunched up version of our solar system.

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The Kepler-90 system is set up like our solar system, with the small planets located close to their star and the big planets farther away. This pattern is evidence that the system’s outer gas planets—which are about the size of Saturn and Jupiter—formed in a way similar to our own.

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But the orbits are much more compact. The orbits of all eight
planets could fit within the distance of Earth’s orbit around our Sun! Sounds
crowded, but think of it this way: It would make for some great planet-hopping.

Kepler-90i was discovered using machine learning.

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Most planets beyond our solar system are too far away to be imaged directly. The Kepler space telescope searches for these exoplanets—those planets orbiting stars beyond our solar system—by measuring how the brightness of a star changes when a planet transits, or crosses in front of its disk. Generally speaking, for a given star, the greater the dip in brightness, the bigger the planet!

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Researchers trained a computer to learn how to identify the faint signal of transiting exoplanets in Kepler’s vast archive of deep-space data. A search for new worlds around 670 known multiple-planet systems using this machine-learning technique yielded not one, but two discoveries: Kepler-90i and Kepler-80g. The latter is part of a six-planet star system located 1,000 light-years away.

This
is just the beginning of a new way of planet hunting.

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Kepler-90 is the first known star system besides our own that has eight planets, but scientists say it won’t be the last. Other planets may lurk around stars surveyed by Kepler. Next, researchers are using machine learning with sophisticated computer algorithms to search for more planets around 150,000 stars in the Kepler database.

In
the meantime, we’ll be doing more searching with telescopes.

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Kepler is the most successful planet-hunting spacecraft to date, with more than 2,500 confirmed exoplanets and many more awaiting verification. Future space missions, like the Transiting Exoplanet Survey Satellite (TESS), the James Webb Space Telescope and Wide-Field Infrared Survey Telescope (WFIRST) will continue the search for new worlds and even tell us which ones might offer promising homes for extraterrestrial life.

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*All images of exoplanets
are artist illustrations.