TESS

The Transiting Exoplanet Survey Satellite

TESS is a NASA Explorer mission launched in 2018 to study exoplanets, or planets orbiting stars outside our solar system. TESS will discover thousands of exoplanets in orbit around the brightest stars in the sky. It will monitor more than 200,000 stars, looking for temporary dips in brightness caused by planets transiting across these stars. This first-ever spaceborne all-sky transit survey will identify a wide range of planets, from Earth-sized to gas giants. The mission will find exoplanet candidates for follow-up observation from missions like the James Webb Space Telescope, which will determine whether these candidates could support life.


For more information, please visit the TESS website.

Content Contact:

Produced Videos

  •
    NASA's Planet-Hunting TESS Catches a Comet Before Starting Science
    2018.08.06
    Before NASA’s Transiting Exoplanet Survey Satellite (TESS) started science operations on July 25, 2018, the planet hunter sent back a stunning sequence of serendipitous images showing the motion of a comet. Taken over the course of 17 hours on July 25, these TESS images helped demonstrate the satellite’s ability to collect a prolonged set of stable periodic images covering a broad region of the sky — all critical factors in finding transiting planets orbiting nearby stars. Over the course of these tests, TESS took images of C/2018 N1, a comet discovered by NASA’s Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) satellite on June 29. The comet, located about 29 million miles (48 million kilometers) from Earth in the southern constellation Piscis Austrinus, is seen to move across the frame from right to left as it orbits the Sun. The comet’s tail, which consists of gases carried away from the comet by an outflow from the Sun called the solar wind, extends to the top of the frame and gradually pivots as the comet glides across the field of view. In addition to the comet, the images reveal a treasure trove of other astronomical activity. The stars appear to shift between white and black as a result of image processing. The shift also highlights variable stars — which change brightness either as a result of pulsation, rapid rotation, or by eclipsing binary neighbors. Asteroids in our solar system appear as small white dots moving across the field of view. Towards the end of the video, one can see a faint broad arc of light moving across the middle section of the frame from left to right. This is stray light from Mars, which is located outside the frame. The images were taken when Mars was at its brightest near opposition, or its closest distance, to Earth. These images were taken during a short period near the end of the mission’s commissioning phase, prior to the start of science operations. The movie presents just a small fraction of TESS’s active field of view. The team continues to fine-tune the spacecraft’s performance as it searches for distant worlds. TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Dr. George Ricker of MIT’s Kavli Institute for Astrophysics and Space Research serves as principal investigator for the mission. Additional partners include Northrop Grumman, based in Falls Church, Virginia; NASA’s Ames Research Center in California’s Silicon Valley; the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts; MIT’s Lincoln Laboratory in Lexington, Massachusetts; and the Space Telescope Science Institute in Baltimore. More than a dozen universities, research institutes and observatories worldwide are participants in the mission.
  •
    TESS Overview
    2018.03.28
  • TESS Shorts
    2018.04.03
    NASA's Transiting Exoplanet Survey Satellite - TESS will fly a never-before-used orbit that completes two circuits around the Earth every time the Moon orbits. This special orbit will allow TESS’s cameras to monitor each patch of sky continuously from nearly a month at a time. To get into this orbit, TESS will make a series of loops culminating in a lunar gravitational-assist, which will give it the push it needs. TESS will reach its orbit about 60 days after launch.
  •
    TESS Undergoes Integration and Testing
    2018.02.08
    The Transiting Exoplanet Survey Satellite (TESS) is the next step in the search for planets outside of our solar system, 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. TESS will survey 200,000 of the brightest stars near the sun to search for transiting exoplanets. The mission is scheduled to launch March 20, 2018, and no later than June 2018.
  •
    TESS Fly Your Exoplanet
    2017.04.03
    The Transiting Exoplanet Survey Satellite (TESS) is taking your art to space! Draw a picture of an exoplanet, or planet orbiting another star, that you think TESS could find. It could fly on the TESS spacecraft, launching in 2018! Download the form at https://tess.gsfc.nasa.gov/fly_your_exoplanet.html and send us your drawing today! Deadline for submissions is November 20, 2017.
  •
    TESS Mission Trailer
    2015.03.20
    This video introduces the Transiting Exoplanet Survey Satellite (TESS). This is a joint mission between NASA and MIT that will scan the entire sky searching for exoplanets, or planets outside our Solar System. Using four state-of-the-art cameras, TESS will monitor over 500,000 stars, looking for changes in their brightness that signal a planet crossing over. The stars TESS looks at will be 30-100 times brighter than those observed by the Kepler satellite, making follow-up observations much easier. Using TESS data, missions like the James Webb Space Telescope can determine specific characteristics of these planets, including whether they could support life. TESS is scheduled to launch in 2017.

Animations

  •
    Kepler Passes Planet-Finding Torch to TESS Animation
    2018.10.30
    After nine years in space, NASA's Kepler has reached its end. The Kepler and K2 missions have discovered over 2,600 confirmed exoplanets so far, including some in the habitable zones of their stars. Kepler used transits--regular dips in a star's brightness caused by orbiting planets--to find new worlds. It's the same method used by NASA's Transiting Exoplanet Survey Satellite. In a way, Kepler has passed the planet-finding torch on to TESS, which will scan nearly the entire sky to continue the hunt for exoplanets.
  •
    TESS Spacecraft Animations
    2018.01.08
    The Transiting Exoplanet Survey Satellite (TESS) will discover thousands of exoplanets in orbit around the brightest stars in the sky. In a two-year survey of the solar neighborhood, TESS will monitor more than 200,000 stars for temporary drops in brightness caused by planetary transits. This first-ever spaceborne all-sky transit survey will identify planets ranging from Earth-sized to gas giants, around a wide range of stellar types and orbital distances. No ground-based survey can achieve this feat.
  •
    TESS Coverage Animations
    2018.03.28
    Animation showing the TESS spacecraft and the coverage of its four cameras. Each camera covers a 24 degrees-square patch of sky and the four cameras are arranged in a vertical strip called an observation sector.
  •
    TESS-Kepler Field-of-View Animation
    2018.03.28
    This animation begins with Kepler's first observation zone and the constellation Cygnus. It adds a single TESS camera field for comparison, and then pulls back to show all four TESS camera fields--called an observation sector--and the amount of sky they cover. The sphere of the sky unwraps into a flat projection and all the regions observed by Kepler appear. TESS's full 2 year coverage appears, starting in the southern hemisphere and ending in the northern. Finally, the map is rewrapped into a sphere.

    Credit: NASA/JPL-Caltech/T. Pyle (IPAC)

  •
    TESS Social Media Products
    2018.04.03
    Looping gif of the TESS spacecraft
  •
    TESS Beauty Pass Animation
    2016.09.20
    Beauty pass of the TESS satellite.
  •
    TESS Rounds Up its First Planets, Snares Far-flung Supernovae
    2019.01.07
    NASA’s Transiting Exoplanet Survey Satellite (TESS) has found three confirmed exoplanets, or worlds beyond our solar system, in its first three months of observations. The mission’s sensitive cameras also captured 100 short-lived changes — most of them likely stellar outbursts — in the same region of the sky. They include six supernova explosions whose brightening light was recorded by TESS even before the outbursts were discovered by ground-based telescopes. The new discoveries show that TESS is delivering on its goal of discovering planets around nearby bright stars. Using ground-based telescopes, astronomers are now conducting follow-up observations on more than 280 TESS exoplanet candidates. The first confirmed discovery is a world called Pi Mensae c about twice Earth’s size. Every six days, the new planet orbits the star Pi Mensae, located about 60 light-years away and visible to the unaided eye in the southern constellation Mensa. The bright star Pi Mensae is similar to the Sun in mass and size. Next is LHS 3884b, a rocky planet about 1.3 times Earth’s size located about 49 light-years away in the constellation Indus, making it among the closest transiting exoplanets known. The star is a cool M-type dwarf star about one-fifth the size of our Sun. Completing an orbit every 11 hours, the planet lies so close to its star that some of its rocky surface on the daytime side may form pools of molten lava. The third — and possibly fourth — planets orbit HD 21749, a K-type star about 80 percent the Sun’s mass and located 53 light-years away in the southern constellation Reticulum. The confirmed planet, HD 21749b, is about three times Earth’s size and 23 times its mass, orbits every 36 days, and has a surface temperature around 300 degrees Fahrenheit (150 degrees Celsius). It is the longest-period transiting planet within 100 light-years of the solar system, and it has the coolest surface temperature of a transiting exoplanet around a star brighter than 10th magnitude, or about 25 times fainter than the limit of unaided human vision. What’s even more exciting are hints the system holds a second candidate planet about the size of Earth that orbits the star every eight days. If confirmed, it could be the smallest TESS planet to date. In its primary two-year mission, TESS will observe nearly the whole sky, providing a rich catalog of worlds around nearby stars. Their proximity to Earth will enable detailed characterization of the planets through follow-up observations from space- and ground-based telescopes. But in its month-long stare into each sector, TESS records many additional phenomena, including comets, asteroids, flare stars, eclipsing binaries, white dwarf stars and supernovae, resulting in an astronomical treasure trove. In the first TESS sector alone, observed between July 25 and Aug. 22, 2018, the mission caught dozens of short-lived, or transient, events, including images of six supernovae in distant galaxies that were later seen by ground-based telescopes. These early observations hold the key to understanding a class of supernovae that serve as an important yardstick for cosmological studies. Type Ia supernovae form through two channels. One involves the merger of two orbiting white dwarfs, compact remnants of stars like the Sun. The other occurs in systems where a white dwarf draws gas from a normal star, gradually gaining mass until it becomes unstable and explodes. Astronomers don’t know which scenario is more common, but TESS could detect modifications to the early light of the explosion caused by the presence of stellar companion.

Raw footage/B-roll

  •
    TESS Launch Footage
    2018.04.26
    NASA’s Transiting Exoplanet Survey Satellite (TESS) was launched April 18 on a SpaceX Falcon 9 rocket, from Cape Canaveral Air Force Station in Florida. TESS is NASA’s next mission to search for planets outside of our solar system, known as exoplanets, including those that could support life. The mission is expected to catalog thousands of planet candidates and vastly increase the current number of known exoplanets. TESS will find the most promising exoplanets orbiting relatively nearby stars, giving future researchers a rich set of new targets for more comprehensive follow-up studies, including the potential to assess their capacity to harbor life.
  •
    TESS Arrives at KSC
    2018.03.05
    NASA's next planet-hunting mission has arrived in Floriday to begin preparation for launch. The Transiting Exoplanet Survey Satellite (TESS) will launch on a SpaceX Falcon 9 rocket from Cape Canaveral Air Force Station in Florida this spring. TESS was delivered Feb. 12 aboard a truck from Orbital ATK in Dulles, Virginia, where it was assembled and tested in 2017. Over the next month, the spacecraft will be prepped for launch at Kennedy's Payload Hazardous Servicing Facility. TESS is the next step in NASA's search for planets outside our solar system, known as exoplanets.
  •
    TESS Solar Array Deploy
    2018.03.13
    NASA's next planet-hunting mission is at the Kennedy Space Center in Florida to begin preparation for launch. The Transiting Exoplanet Survey Satellite (TESS) will launch on a SpaceX Falcon 9 rocket from Cape Canaveral Air Force Station in Florida this spring. TESS is being prepped for launch at Kennedy's Payload Hazardous Servicing Facility. TESS is the next step in NASA's search for planets outside our solar system, known as exoplanets.
  •
    TESS Spacecraft Beauty Shots
    2017.11.20
    The fully integrated Transiting Exoplanet Survey Satellite (TESS), which will launch in 2018 to find thousands of new planets orbiting other stars.
  •
    TESS Integration Prep B-Roll
    2017.05.18
    The TESS spacecraft being prepared for integration of the TESS instrument at Orbital ATK.
  •
    TESS Camera Mounting Timelapse
    2017.08.03
    The four TESS cameras being mounted to the camera plate in preparation for integration to spacecraft at Orbital ATK in Dulles, Va.
  •
    TESS Camera Mounting Photos
    2017.08.03
    TESS cameras being mounted to the camera plate at Orbital ATK in Dulles, Va. before installation onto the spacecraft.
  •
    TESS Camera Integration Photos
    2017.09.11
    The TESS cameras being integrated onto the spacecraft at Orbital ATK in Dulles, Va.
  •
    TESS Camera Integration B-Roll
    2017.09.13
    Footage of TESS cameras being integrated onto spacecraft at Orbital ATK in Dulles, Va.
  •
    TESS Solar Array Deployment Photos
    2017.10.26
    Photos of the TESS solar arrays being deployed at Orbital ATK in Dulles, Va. before the assembled spacecraft is moved into testing.
  •
    TESS Vibration Testing Photos
    2017.10.26
    Photos of TESS spacecraft being tested on vibration table at Orbital ATK in Dulles, Va.
  •
    TESS Solar Array Deployment B-Roll
    2017.10.27
    Video Footage of the TESS spacecraft solar arrays being deployed for testing at Orbital ATK in Dulles, Va.

Still images

  •
    NASA’s TESS Releases First Science Image
    2018.09.17
    NASA’s newest planet hunter, the Transiting Exoplanet Survey Satellite (TESS), is now providing valuable data to help scientists discover and study exciting new exoplanets, or planets beyond our solar system. Part of the data from TESS’s initial science orbit includes a detailed picture of the southern sky taken with all four of the spacecraft’s wide-field cameras. This “first light” science image captures a wealth of stars and other objects, including systems previously known to have exoplanets. TESS acquired the image using all four cameras during a 30-minute period on Tuesday, Aug. 7. The black lines in the image are gaps between the camera detectors. The small bright dot above the Small Magellanic Cloud is a globular cluster — a spherical collection of hundreds of thousands of stars — called NGC 104, also known as 47 Tucanae because of its location in the southern constellation Tucana, the Toucan. Two stars, Beta Gruis and R Doradus, are so bright they saturate an entire column of pixels on the detectors of TESS’s second and fourth cameras, creating long spikes of light. TESS’s cameras, designed and built by MIT’s Lincoln Laboratory in Lexington, Massachusetts, and the MIT Kavli Institute, monitor large swaths of the sky to look for transits. Transits occur when a planet passes in front of its star as viewed from the satellite’s perspective, causing a regular dip in the star’s brightness. TESS will spend two years monitoring 26 such sectors for 27 days each, covering 85 percent of the sky. During its first year of operations, the satellite will study the 13 sectors making up the southern sky. Then TESS will turn to the 13 sectors of the northern sky to carry out a second year-long survey.
  •
    TESS Artist Concept Images
    2017.09.22
    Artist concept images of the Transiting Exoplanet Survey Satellite.
  •
    TESS Spacecraft Beauty Shots
    2017.11.20
    The fully integrated Transiting Exoplanet Survey Satellite (TESS), which will launch in 2018 to find thousands of new planets orbiting other stars.

Presentation Resources

  •
    Exoplanet Transit Animations
    2018.08.06
    When a planet passes directly between a star and its observer, it dims the star's light by a measurable amount. This animation shows a single planet and the corresponding light curve.
  •
    Exoplanet Animations
    2016.09.20
    Animation imagining what an ice-covered exoplanet might look like.
  •
    HD 189733b Exoplanet Animation
    2012.06.28
    The exoplanet HD 189733b lies so near its star that it completes an orbit every 2.2 days. In late 2011, NASA's Hubble Space Telescope found that the planet's upper atmosphere was streaming away at speeds exceeding 300,000 mph. Just before the Hubble observation, NASA's Swift detected the star blasting out a strong X-ray flare, one powerful enough to blow away part of the planet's atmosphere.
  •
    Exoplanet scale
    2017.01.13
    This illustration compares the sizes of various exoplanets with Earth and the Moon.

    Credit: NASA's Goddard Space Flight Center

  •
    TESS AAS Hyperwall Presentation January 2018
    2018.01.07
  • SEEC AAS Hyperwall Presentation January 2018
    2018.03.15
  • TESS Rounds Up its First Planets, Snares Far-flung Supernovae
    2019.01.07
    NASA’s Transiting Exoplanet Survey Satellite (TESS) has found three confirmed exoplanets, or worlds beyond our solar system, in its first three months of observations. The mission’s sensitive cameras also captured 100 short-lived changes — most of them likely stellar outbursts — in the same region of the sky. They include six supernova explosions whose brightening light was recorded by TESS even before the outbursts were discovered by ground-based telescopes. The new discoveries show that TESS is delivering on its goal of discovering planets around nearby bright stars. Using ground-based telescopes, astronomers are now conducting follow-up observations on more than 280 TESS exoplanet candidates. The first confirmed discovery is a world called Pi Mensae c about twice Earth’s size. Every six days, the new planet orbits the star Pi Mensae, located about 60 light-years away and visible to the unaided eye in the southern constellation Mensa. The bright star Pi Mensae is similar to the Sun in mass and size. Next is LHS 3884b, a rocky planet about 1.3 times Earth’s size located about 49 light-years away in the constellation Indus, making it among the closest transiting exoplanets known. The star is a cool M-type dwarf star about one-fifth the size of our Sun. Completing an orbit every 11 hours, the planet lies so close to its star that some of its rocky surface on the daytime side may form pools of molten lava. The third — and possibly fourth — planets orbit HD 21749, a K-type star about 80 percent the Sun’s mass and located 53 light-years away in the southern constellation Reticulum. The confirmed planet, HD 21749b, is about three times Earth’s size and 23 times its mass, orbits every 36 days, and has a surface temperature around 300 degrees Fahrenheit (150 degrees Celsius). It is the longest-period transiting planet within 100 light-years of the solar system, and it has the coolest surface temperature of a transiting exoplanet around a star brighter than 10th magnitude, or about 25 times fainter than the limit of unaided human vision. What’s even more exciting are hints the system holds a second candidate planet about the size of Earth that orbits the star every eight days. If confirmed, it could be the smallest TESS planet to date. In its primary two-year mission, TESS will observe nearly the whole sky, providing a rich catalog of worlds around nearby stars. Their proximity to Earth will enable detailed characterization of the planets through follow-up observations from space- and ground-based telescopes. But in its month-long stare into each sector, TESS records many additional phenomena, including comets, asteroids, flare stars, eclipsing binaries, white dwarf stars and supernovae, resulting in an astronomical treasure trove. In the first TESS sector alone, observed between July 25 and Aug. 22, 2018, the mission caught dozens of short-lived, or transient, events, including images of six supernovae in distant galaxies that were later seen by ground-based telescopes. These early observations hold the key to understanding a class of supernovae that serve as an important yardstick for cosmological studies. Type Ia supernovae form through two channels. One involves the merger of two orbiting white dwarfs, compact remnants of stars like the Sun. The other occurs in systems where a white dwarf draws gas from a normal star, gradually gaining mass until it becomes unstable and explodes. Astronomers don’t know which scenario is more common, but TESS could detect modifications to the early light of the explosion caused by the presence of stellar companion.

Live Events

  •
    NASA Preparing to Launch New Planet-Hunting Mission Live Shots
    2018.04.10
    NASA Preparing to Launch New Planet Hunting Mission Next Week
    Mission Expected to Discover Thousands of New Worlds Orbiting Nearby Stars
    NASA Scientists Available to Speak On the Hunt For New Worlds
     The hunt is on to discover new and exciting worlds! NASA’s Transiting Exoplanet Survey Satellite – TESS – is scheduled to launch April 16 to find thousands of planets orbiting stars outside our solar system, known as exoplanets. In the past ten years, NASA has discovered and studied thousands of these planets – including the TRAPPIST-1 system, which could have the ingredients to support life. TESS is expected to add thousands more planets to this growing list during its two-year mission, looking at the nearest and brightest stars in our galaxy to see if there are worlds hiding in their light.

    From molten lava and frigid icy planets, to bizarre places that rain rubies and sapphires and water-covered worlds, the possibilities of new worlds for the planet-hunter to find are limitless. Are Earth and the other planets in our solar system unique? Join NASA scientists from 6:00 a.m. to 12:00 p.m. EDT on Tuesday, April 10 – days before the launch – as they share some of the exciting discoveries they hope to find with the TESS mission.

    TESS will find promising planets that other NASA telescopes – like the Hubble Space Telescope and future James Webb Space Telescope – could look at in more detail to determine what their atmospheres are made of, and whether these unknown worlds could potentially support life. Suggested Questions:
    1. What is an exoplanet and why are scientists excited about them?
    2. How will this new mission help NASA in the search for life?
    3. Will this planet-hunter change the way we look at the stars in the night sky?
    4. Previous telescopes have found really unusual worlds. What kinds of planets are you looking forward to TESS discovering?
    5. Where can we learn more?
    Questions for longer interviews:
    1. Where will TESS orbit?
    2. What has been the biggest surprise in searching for exoplanets?
    3. How will TESS detect planets?
    4. What makes TESS different than other planet hunter missions?
    5. What does it look like when a planet crosses in front of the parent star?
    Live Shot Details: Location: NASA’s Goddard Space Flight Center/Greenbelt, Maryland

    Scientists:
    Dr. Paul Hertz / NASA Director of Astrophysics
    —or—
    Dr. Joshua Schlieder / NASA Scientist
    —or—
    Dr. Jennifer Burt / MIT Torres postdoctoral fellow
    —or—
    Natalia Guerrero / MIT Kavli TESS Objects of Interest Deputy Manager [ en Español ]z

  •
    Exoplanet Live Shots 2.23.17
    2017.02.21
    NASA's Spitzer Space Telescope has revealed the first known system of seven Earth-size planets around a single star. Three of these planets are firmly located in the habitable zone, the area around the parent star where a rocky planet is most likely to have liquid water. You can find graphics HERE that go with this story. The discovery sets a new record for greatest number of habitable-zone planets found around a single star outside our solar system. All of these seven planets could have liquid water–key to life as we know it–under the right atmospheric conditions, but the chances are highest with the three in the habitable zone.
  •
    Mercury Transit Live Shots May 9, 2016
    2016.05.02

    NASA will broadcast a stunning view of Mercury on May 9 as it journeys across the sun. The event, known as a transit, occurs when Mercury passes directly between Earth and the sun. This rare phenomenon will cause Mercury to look like a black dot gliding across the sun’s face. Mercury’s last transit was in 2006, and it won’t happen again until 2019!

    Starting at 7:12 a.m. EDT, Mercury will spend more than seven hours travelling across the sun. NASA’s Solar Dynamics Observatory will take the first near real time, ultra-high definition images ever for this event. This is also an opportunity for NASA scientists to fine tune the spacecraft’s cameras, using a method that can only be done during a transit.

  •
    2017 Spring Equinox Live Shots
    2017.03.15
    March 20 Equinox Marks the Start of Spring in the Northern Hemisphere

    Dance of the Solar System is the First Solar Event of 2017

    Stay Tuned for the Big Event of 2017, the August Solar Eclipse!

    It may not feel like it this week in parts of the country, but spring begins in just a few days. March 20 kicks off the first day of astronomical spring in the Northern Hemisphere. On March 20, the day of the spring Equinox, the sun will pass directly over the Earth’s equator, giving the entire planet equal hours of day and night. This is the seasonal marker in Earth’s orbit around the sun when daylight hours begin to get longer than night.

    This dance of the solar system is just one celestial event we’ll see this year. On August 21 all 50 states in the U.S. will be in prime position to see a partial or even a total solar eclipse, which happens when the moon is in perfect position to blot out the sun’s bright disk. The last time the U.S. saw a coast-to-coast solar eclipse was in 1918! The path of totality runs from Oregon to South Carolina.

    NASA will lead an unprecedented science initiative during the eclipse that will draw on the collaboration of the public to help collect images, data and even temperature readings from across the nation during the hour-and-a-half it takes to cross the continent.

  •
    NASM 2016: The Search For Life
    2017.02.11
    On September 21, 2016, NASA scientists and stakeholders came together at the Smithsonian National Air and Space Museum for a presentation on the agency’s search for life beyond Earth. “The Search for Life” featured presentations from some of NASA’s leading scientists, including the late former astronaut, Dr. Piers Sellers. Through compelling visualizations, “The Search for Life” takes you on a journey through the solar system and beyond, exploring the possibility of life existing on Mars, the solar system’s outer moons, and exoplanets.

Related Items

  •
    Alien Atmospheres
    2013.12.03
    Since the early 1990's, astronomers have known that extrasolar planets, or "exoplanets," orbit stars light-years beyond our own solar system. Although most exoplanets are too distant to be directly imaged, detailed studies have been made of their size, composition, and even atmospheric makeup - but how? By observing periodic variations in the parent star's brightness and color, astronomers can indirectly determine an exoplanet's distance from its star, its size, and its mass. But to truly understand an exoplanet astronomers must study its atmosphere, and they do so by splitting apart the parent star's light during a planetary transit.
  •
    Looking for the Shadows of New Worlds
    2015.10.30
    Astronomers have used many different methods to discover planets beyond the solar system, but the most successful by far is transit photometry, which measures changes in a star's brightness caused by a mini-eclipse. When a planet crosses in front of its star along our line of sight, it blocks some of the star's light. If the dimming lasts for a set amount of time and occurs at regular intervals, it likely means an exoplanet is passing in front of, or transiting, the star once every orbital period. NASA’s Kepler Space Telescope has used this technique to become the most successful planet-hunting spacecraft to date, with more than a thousand established discoveries and many more awaiting confirmation. Missions carrying improved technology are now planned, but how much more can they tell us about alien planetary systems similar to our own? A great deal, according to recently published studies by Michael Hippke at the Institute for Data Analysis in Neukirchen-Vluyn, Germany, and Daniel Angerhausen, a postdoctoral researcher at NASA's Goddard Space Flight Center in Greenbelt, Maryland. They show that in the best-case scenarios upcoming missions could uncover planetary moons, ringed worlds similar to Saturn, and even large collections of asteroids.
  •
    Join the Search for New Nearby Worlds
    2017.02.15
    A new website funded by NASA lets the public search for new worlds in the outer reaches of our solar system and in neighboring interstellar space. The website, called Backyard Worlds: Planet 9, allows everyone to participate in the search though brief movies made from images captured by NASA's Wide-field Infrared Survey Explorer (WISE) mission. The movies highlight sources that have gradually moved across the sky. The new website uses WISE all-sky data to search for unknown objects in and beyond our own solar system. In 2016, astronomers at the California Institute of Technology showed that several distant solar system objects possessed orbital features indicating they were affected by the gravity of an as-yet-undetected planet, which the researchers nicknamed "Planet Nine." If Planet Nine exists and is as bright as some predictions, it could show up in WISE data. The search also may discover more distant objects like brown dwarfs, sometimes called failed stars, in nearby interstellar space. These strange objects form like stars but evolve like planets, the coldest ones being much like Jupiter. On the website, people around the world can work their way through millions of "flipbooks," which are brief animations showing how small patches of the sky changed over several years. Moving objects flagged by users will be prioritized by the science team for later follow-up observations by professional astronomers. Participants will share credit for their discoveries in any scientific publications that result from the project.
  •
    Mercury Transit May 9, 2016
    2016.04.25
    This animation shows the May 9, 2016 transit of Mercury across the face of the Sun.