• ESA uses cookies to track visits to our website only, no personal information is collected.
    By continuing to use the site you are agreeing to our use of cookies. OK
    Find out more about our cookie policy.
    • → European Space Agency

    • About Science & Technology

    • For Public

    • For Educators

    • ESA

    • Science & Technology

    • CoRoT

    • Missions
    • Show All Missions
    • Mission Home
    • Summary
    • Fact Sheet
    • Mission Science
    • Spacecraft
    • Instruments
    • Mission Operations
    • Resources
    • News Archive
    • Multimedia Gallery
    • Publications Archive
    • Calendar
    • Services
    • Contact Us
    • Subscribe
    • RSS feed
    • Terms and Conditions

    CoRoT team announces detection of smallest exoplanet to date

    03 February 2009

    An exoplanet barely larger than the Earth has been discovered by the CoRoT satellite. This was announced on 3 February at a press conference during the First CoRoT International Symposium held in Paris.

    The dip in the light curve indicates the presence of a transiting object: CoRoT-Exo-7b

    The planet, CoRoT-Exo-7b, has a diameter less than twice that of Earth making this the smallest exoplanet radius measured yet. It orbits its parent star, (CoRoT-Exo-7: a main-sequence K-type star at a distance of 140pc) every 20 hours. The surface temperature is estimated to be of order 1000-1500°C.

    Although the density of the planet has not yet been well determined preliminary indications are that it may be rocky and covered in liquid lava. An alternative proposal is that it may be a ‘sauna planet’ of half water (in a superheated state) and half rock.

    This exoplanet was first seen by CoRoT last spring but a campaign of ground-based observations was needed to confirm its nature.

    To date more than 330 exoplanets have been detected. Most of these are giant, gaseous planets. The discovery of CoRoT-Exo-7b is significant because recent measurements have indicated the existence of small-mass planets but their size has remained undetermined until now.

    Related publication
    The findings will appear in 'Transiting exoplanets from the CoRoT space mission VII. COROT-Exo-7b: The first super-earth with radius characterized' by A. Léger , D. Rouan , J. Schneider , R. Alonso , B. Samuel , E. Guenther , M. Deleuil , H.J. Deeg , M. Fridlund, et al. to be submitted to Astronomy and Astrophysics.


    Last Update: 04 February 2009

    • Shortcut URL
    • http://sci.esa.int/jump.cfm?oid=44131
    • Images And Videos
    • Light curve revealing transit of CoRoT-7b
    • Related Links
    • Basic data on CoRoT-Exo-7b
    • The Extrasolar Planets Encyclopaedia
    • CoRoT discovers smallest exoplanet yet, with a surface to walk on
    • First CoRoT International Symposium
    • CoRoT at CNES

    Connect with us

    • RSS
    • Youtube
    • Twitter
    •  Flickr
    • Google+
    • Livestream
    • Subscribe
    • Appstore
    • Twitter-2

    Follow ESA science