JWST - Blog Posts

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.)

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:

And this is what we see with infrared light:

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.

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:

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:

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.

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.

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

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

...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. 

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

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

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

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.

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!

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

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

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.

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.

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.

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

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.

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.

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!

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

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Researchers Just Found (For The First Time) An 8th Planet Orbiting A Star Far, Far Away

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.

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.

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.

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.

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.

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!

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.

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.

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.

Why Webb Needs to Chill

Our massive James Webb Space Telescope just recently emerged from about 100 days of cryogenic testing to make sure it can work perfectly at incredibly cold temperatures when it’s in deep space. 

How cold did it get and why? Here’s the whole scoop...

Webb is a giant infrared space telescope that we are currently building. It was designed to see things that other telescopes, even the amazing Hubble Space Telescope, can’t see.  

Webb’s giant 6.5-meter diameter primary mirror is part of what gives it superior vision, and it’s coated in gold to optimize it for seeing infrared light.  

Why do we want to see infrared light?

Lots of stuff in space emits infrared light, so being able to observe it gives us another tool for understanding the universe. For example, sometimes dust obscures the light from objects we want to study – but if we can see the heat they are emitting, we can still “see” the objects to study them.

It’s like if you were to stick your arm inside a garbage bag. You might not be able to see your arm with your eyes – but if you had an infrared camera, it could see the heat of your arm right through the cooler plastic bag.

Credit: NASA/IPAC

With a powerful infrared space telescope, we can see stars and planets forming inside clouds of dust and gas.

We can also see the very first stars and galaxies that formed in the early universe. These objects are so far away that…well, we haven’t actually been able to see them yet. Also, their light has been shifted from visible light to infrared because the universe is expanding, and as the distances between the galaxies stretch, the light from them also stretches towards redder wavelengths. 

We call this phenomena “redshift.”  This means that for us, these objects can be quite dim at visible wavelengths, but bright at infrared ones. With a powerful enough infrared telescope, we can see these never-before-seen objects.

We can also study the atmospheres of planets orbiting other stars. Many of the elements and molecules we want to study in planetary atmospheres have characteristic signatures in the infrared.

Because infrared light comes from objects that are warm, in order to detect the super faint heat signals of things that are really, really far away, the telescope itself has to be very cold. How cold does the telescope have to be? Webb’s operating temperature is under 50K (or -370F/-223 C). As a comparison, water freezes at 273K (or 32 F/0 C).

How do we keep the telescope that cold? 

Because there is no atmosphere in space, as long as you can keep something out of the Sun, it will get very cold. So Webb, as a whole, doesn’t need freezers or coolers - instead it has a giant sunshield that keeps it in the shade. (We do have one instrument on Webb that does have a cryocooler because it needs to operate at 7K.)

Also, we have to be careful that no nearby bright things can shine into the telescope – Webb is so sensitive to faint infrared light, that bright light could essentially blind it. The sunshield is able to protect the telescope from the light and heat of the Earth and Moon, as well as the Sun.  

Out at what we call the Second Lagrange point, where the telescope will orbit the Sun in line with the Earth, the sunshield is able to always block the light from bright objects like the Earth, Sun and Moon.

How do we make sure it all works in space? 

By lots of testing on the ground before we launch it. Every piece of the telescope was designed to work at the cold temperatures it will operate at in space and was tested in simulated space conditions. The mirrors were tested at cryogenic temperatures after every phase of their manufacturing process.

The instruments went through multiple cryogenic tests at our Goddard Space Flight Center in Maryland.

Once the telescope (instruments and optics) was assembled, it even underwent a full end-to-end test in our Johnson Space Center’s giant cryogenic chamber, to ensure the whole system will work perfectly in space.  

What’s next for Webb? 

It will move to Northrop Grumman where it will be mated to the sunshield, as well as the spacecraft bus, which provides support functions like electrical power, attitude control, thermal control, communications, data handling and propulsion to the spacecraft.

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

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Solar System: Things to Know This Week

What's next for NASA? A quick look at some of the big things coming up:

1. We will add to our existing robotic fleet at the Red Planet with the InSight Mars lander set to study the planet's interior.

This terrestrial planet explorer will address one of the most fundamental issues of planetary and solar system science - understanding the processes that shaped the rocky planets of the inner solar system (including Earth) more than four billion years ago.

2. The Mars 2020 rover will look for signs of past microbial life, gather samples for potential future return to Earth.

The Mars 2020 mission takes the next step by not only seeking signs of habitable conditions on the Red Planet in the ancient past, but also searching for signs of past microbial life itself. The Mars 2020 rover introduces a drill that can collect core samples of the most promising rocks and soils and set them aside in a "cache" on the surface of Mars.

3. The James Webb Space Telescope will be the premier observatory of the next decade, studying the history of our Universe in infrared.

Webb will study every phase in the history of our Universe, ranging from the first luminous glows after the Big Bang, to the formation of solar systems capable of supporting life on planets like Earth, to the evolution of our own solar system.

4. The Parker Solar Probe will "touch the Sun," traveling closer to the surface than any spacecraft before.

This spacecraft, about the size of a small car, will travel directly into the sun's atmosphere about 4 million miles from our star's surface. Parker Solar Probe and its four suites of instruments – studying magnetic and electric fields, energetic particles, and the solar wind – will be protected from the Sun’s enormous heat by a 4.5-inch-thick carbon-composite heat shield.

5. Our OSIRIS-REx spacecraft arrives at the near-Earth asteroid Bennu in August 2018, and will return a sample for study in 2023.

This mission will help scientists investigate how planets formed and how life began, as well as improve our understanding of asteroids that could impact Earth.

6. Launching in 2018, the Transiting Exoplanet Survey Satellite (TESS) will search for planets around 200,000 bright, nearby stars.

The Transiting Exoplanet Survey Satellite (TESS) is the next step in the search for planets outside of our solar system (exoplanets), including those that could support life. The mission will find exoplanets that periodically block part of the light from their host stars, events called transits.

7. A mission to Jupiter's ocean-bearing moon Europa is being planned for launch in the 2020s.

The mission will place a spacecraft in orbit around Jupiter in order to perform a detailed investigation of Europa -- a world that shows strong evidence for an ocean of liquid water beneath its icy crust and which could host conditions favorable for life.

8. We will launch our first integrated test flight of the Space Launch System rocket and Orion spacecraft, known as Exploration Mission-1.

The Space Launch System rocket will launch with Orion atop it. During Exploration Mission-1, Orion will venture thousands of miles beyond the moon during an approximately three week mission.

9. We are looking at what a flexible deep space gateway near the Moon could be.

We’ve issued a draft announcement seeking U.S. industry-led studies for an advanced solar electric propulsion (SEP) vehicle capability. The studies will help define required capabilities and reduce risk for the 50 kilowatt-class SEP needed for the agency’s near-term exploration goals.

10. Want to know more? Read the full story.

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Webb 101: 10 Facts about the James Webb Space Telescope

Did you know…?

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

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

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

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

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

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

Credit: Northrop Grumman

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

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

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

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

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

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

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

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

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The James Webb Space Telescope: A Story of Art & Science

Artists of all kinds were invited to apply for the chance to visit our Goddard Space Flight Center to be inspired by the giant, golden, fully-assembled James Webb Space Telescope mirror.

Art/Photo Credit: Jedidiah Dore

Webb has a mirror that is nearly 22 feet high and (to optimize it for infrared observations) is covered in a microscopic layer of actual gold.

Art/Photo Credit: Susan Lin

Because of Webb’s visually striking appearance, the project hosted a special viewing event on Wednesday, Nov. 2, 2016.

Photo Credit: Maggie Masetti

There was an overwhelming response to the event invitation and ultimately twenty-four people were selected to attend. They represented a broad range of artistic media and styles, including: watercolor, 3D printed sculpture, silk screening, acrylics, sumi-e (East Asian brush technique), comics, letterpress, woodwork, metalwork, jewelry making, fiber art, ink, mural painting, kite-making, tattooing, scientific illustration, poetry, songwriting, and video making.

Art/Photo Credit: Sue Reno

Project scientists and engineers spoke with visitors to give context to what they were seeing and explain why Webb is an engineering marvel, and how it will change our view of the universe. 

Among other things, Webb will see the first stars and galaxies that formed in the early universe and help us to better understand how planetary systems form and evolve. It will help us answer questions about who we, as humans, are and where we came from.

Art Credit: Jessica Lee Photo Credit: Maggie Masetti

The artists spent several hours sitting right in front of the telescope, where they sketched, painted, took photos and even filmed a music video.

Art Credit: Joanna Barnum Photo Credit: Maggie Masetti

While some of the pieces of art are finished, most of the artists went home with their heads full of ideas and sketchbooks full of notes. Stay tuned for more info on where you can see their final works displayed!

Art/Photo Credit: Susan Lin

Finished art from the event continues to be added HERE.

The James Webb Space Telescope is finishing environmental testing at our Goddard Space Flight Center in Greenbelt, Maryland. Next it will head to our Johnson Space Center in Houston for an end-to-end test at cryogenic temperatures. After that, it goes to Northrop Grumman to be mated with the giant tennis court-sized sunshield and the spacecraft bus.  The observatory will launch in October of 2018 from a European Space Agency (ESA) launch site in French Guiana, aboard an Ariane 5 rocket.  Webb is a collaboration of NASA, ESA, and the Canadian Space Agency (CSA).

Follow Webb on Facebook, Twitter and Instagram.

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A Space Odyssey: 21 Years of Searching for Another Earth

There are infinite worlds both like and unlike this world of ours. We must believe that in all worlds there are living creatures and plants and other things we see in this world. – Epicurus, c. 300 B.C.

Are we alone? Are there other planets like ours? Does life exist elsewhere in the universe?

These are questions mankind has been asking for years—since the time of Greek philosophers. But for years, those answers have been elusive, if not impossible to find.

The month of October marks the 21st anniversary of the discovery of the first planet orbiting another sun-like star (aka. an exoplanet), 51 Pegasi b or “Dimidium.” Its existence proved that there were other planets in the galaxy outside our solar system.*

Even more exciting is the fact that astronomers are in hot pursuit of the first discovery of an Earth-like exoplanet orbiting a star other than the sun. The discovery of the so-called "blue dot" could redefine our understanding of the universe and our place in it, especially if astronomers can also find signs that life exists on that planet's surface.

Astronomy is entering a fascinating era where we're beginning to answer tantalizing questions that people have pondered for thousands of years.

Are we alone?

In 1584, when the Catholic monk Giordano Bruno asserted that there were "countless suns and countless earths all rotating around their suns," he was accused of heresy.

But even in Bruno's time, the idea of a plurality of worlds wasn't entirely new. As far back as ancient Greece, humankind has speculated that other solar systems might exist and that some would harbor other forms of life.

Still, centuries passed without convincing proof of planets around even the nearest stars.

Are there other planets like ours?

The first discovery of a planet orbiting a star similar to the sun came in 1995. The Swiss team of Michel Mayor and Didier Queloz of Geneva announced that they had found a rapidly orbiting gas world located blisteringly close to the star 51 Pegasi.

This announcement marked the beginning of a flood of discoveries. Exotic discoveries transformed science fiction into science fact:

a pink planet

worlds with two or even three suns

a gas giant as light as Styrofoam

a world in the shape of an egg

a lava planet

But what about another Earth?

Our first exoplanet mission**, Kepler, launched in 2009 and revolutionized how astronomers understand the universe and our place in it. Kepler was built to answer the question—how many habitable planets exist in our galaxy?

And it delivered: Thousands of planet discoveries poured in, providing statistical proof that one in five sun-like stars (yellow, main-sequence G type) harbor Earth-sized planets orbiting in their habitable zones– where it’s possible liquid water could exist on their surface.

Now, our other missions like the Hubble and Spitzer space telescopes point at promising planetary systems (TRAPPIST-1) to figure out whether they are suitable for life as we know it.

Does life exist elsewhere in the universe?

Now that exoplanet-hunting is a mainstream part of astronomy, the race is on to build instruments that can find more and more planets, especially worlds that could be like our own.

Our Transiting Exoplanet Survey Satellite (TESS), set for launch in 2017-2018, will look for super-Earth and Earth-sized planets around stars much closer to home. TESS will find new planets the same way Kepler does—via the transit method—but will cover 400 times the sky area.

The James Webb Space Telescope, to launch in 2018, wil be our most powerful space telescope to date. Webb will use its spectrograph to look at exoplanet atmospheres, searching for signs of life.

We still don’t know where or which planets are in the habitable zones of the nearest stars­ to Earth. Searching out our nearest potentially habitable neighbors will be the next chapter in this unfolding story.

*The first true discovery of extrasolar planets was actually a triplet of dead worlds orbiting the remains of an exploded star, called a pulsar star. Two of three were found by Dr. Alexander Wolszczan in 1992– a full three years before Dimidium’s discovery. But because they are so strange, and can’t support life as we know it, most scientists would reserve the “first” designation for a planet orbiting a normal star.

** The French CoRoT mission, launched in 2006, was the first dedicated exoplanet space mission. It has contributed dozens of confirmed exoplanets to the ranks and boasts a roster of some of the most well-studied planets outside our solar system.

To stay up-to-date on our latest exoplanet discoveries, visit: https://exoplanets.nasa.gov

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The James Webb Space Telescope

Like your backyard telescope, just MUCH more powerful

We’re building the world’s biggest space telescope ever - the James Webb Space Telescope. Webb will look back in time, studying the very first galaxies ever formed. While Webb doesn’t have a tube like your typical backyard telescope, because it's also a reflector telescope it has many of the same parts! Webb has mirrors (including a primary and a secondary) just like a small reflector telescope, only its mirrors are massive (6.5 meters across) and coated in gold (which helps us reflect infrared light).

How does a reflector telescope work? Light is bounced from the primary to the smaller secondary mirror, and then directed to your eye:

Webb works pretty much the same way!

Taking the place of your eye to the eyepiece is a package of science instruments, including cameras and spectrographs, which will capture the light directed into them by the telescope’s mirrors.    

In order to install these instruments, we had to move the telescope structure upside down… an impressive sight!

Once Webb was in place on the assembly stand in the cleanroom, the team at Goddard Space Flight Center installed the instrument module (which we call the ISIM, or Integrated Science Instrument Module), with surgical precision. ISIM has four instruments, three of which were contributed by our partners, the European Space Agency and the Canadian Space Agency. 

All four will detect infrared light from stars and galaxies as far away as 13.6 billion light years. In addition to seeing these first sources of light in the early Universe, Webb will look at stars and planetary systems being formed in clouds of dust and gas. It will also examine the atmospheres of planets around other stars – perhaps we will find an atmosphere similar to Earth’s!

Here is an image with the science instruments being lowered into their spot behind the primary mirror. You can see the golden mirror is face-down.

Here’s another perspective of the instruments being fit into the telescope. 

What you've seen come together above is just the telescope part of the James Webb Space Telescope mission – next comes putting together the rest of the observatory. This includes our massive tennis court-sized sunshield (which acts like the tube-part of your backyard telescope, protecting the mirrors from stray light and heat), as well as the parts that do things like power the telescope and let us communicate with it.

It actually takes several weeks for Webb to completely unfold into its full deployment!

Follow us on Twitter, Facebook and Instagram for updates on our progress. You can also visit our site for more information: http://jwst.nasa.gov

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Photo Credit #1: NASA/Chris Gunn. Photo Credit #2: NASA/Desiree Stover