Transiting Exoplanet Survey Satellite (TESS)


    The Transiting Exoplanet Survey Satellite (TESS) is designed to discover thousands of exoplanets in orbit around the brightest dwarf stars in the sky. In its prime mission, a two-year survey of the solar neighborhood, TESS monitored the brightness of stars for periodic drops caused by planet transits. The prime mission ended on July 4, 2020 and TESS is now in an extended mission. TESS is finding planets ranging from small, rocky worlds to giant planets, showcasing the diversity of planets in the galaxy.

    Astronomers predict that TESS will discover dozens of Earth-sized planets and up to 500 planets less than twice the size of Earth. In addition to Earth-sized planets, TESS is expected to find some 20,000 exoplanets in its two-year prime mission. TESS will find upwards of 17,000 planets larger than Neptune.

    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.

    More on the mission from Goddard ›
    Visit the mission science team at MIT ›

    Worlds TESS Could Discover

    Worlds TESS Could Discover

    • Neptunian worlds, similar to Uranus or Neptune in our solar system. Example: HAT -P-26b
    • Terrestrial planets, which are rocky worlds, with iron-rich cores, like Mercury, Venus, Earth and Mars in our solar system. Example: Kepler-438b
    • Gas giants, large planets with low density and composed mainly of hydrogen and helium, similar to Jupiter or Saturn in our solar system. Example: 14 Andromedae b
    • Super Earths, a class of planets unlike any in our solar system—more massive than Earth yet lighter than gas giants like Neptune, which can be made of gas, rock or a combination of both. Example: 55 Cancri e
    • Hot Jupiters, exoplanets that are roughly the same mass as Jupiter (or larger), but which orbit extremely close to their star. Example: 51 Pegasi b
    • Planets around Dwarf Stars, which have a mere fraction of the Sun's mass and luminosity but are more than 10 times as numerous. Example: the TRAPPIST-1 system

    TESS Spacecraft Model


    TESS 3D Spacecraft

    Explore the components and functions of the Transiting Exoplanet Survey Satellite with this interactive presentation.

    Latest TESS News

    • Go here for the latest news and discoveries from NASA’s new mission to search for new worlds around 200,000 of the brightest stars near the Sun.

    • Detailed information on the TESS mission: its science goals, background information on exoplanets, a glossary of terms, and more.

    • This interactive experience provides an overview of the most common techniques used to find planets beyond our solar system.

    People of TESS


    More Resources

    The ABCs of Exoplanets

    New Worlds Atlas - an interactive encylopedia of exoplanets

    Historic Timeline - a guide to the history of exoplanet discoveries

    Eyes on Exoplanets - 3D visualization tool

    Tess News