CoRoT


Convection, Rotation and Transits


A space mission dedicated to the seismology of stars and to the study of extrasolar planets

Launch (27 Dec. 2006 14h 23m 38.7s UT):

update: 4 June 2008

CoRoT events

2008
04 Jun A small depth light curve
20 May CoRoT communiqué
19 May one compact brown dwarf CoRoT-Exo-3 b and two planets CoRoT-Exo-4 b and CoRoT-Exo-5 b detected

2007
20 Dec CoRoT-Exo-2 b: second CoRoT planet. Press release (in French)
05 Nov 300 days in orbit.
02 May CoRoT-Exo-1b: first planet detetected by CoRoT.
06 Fe. First science observations (in French).
02 Feb Image with fine pointing. (in French)
30 Jan Fine pointing has started. Performances 20% better than initial specifications.
21 Jan CoRoT has mapped the South Atlantic Anomaly.
19 Jan First image of CoRoT on the sky.
17 Jan./b> The shutter has been successfully opened today at 15h30 UT. First images from the sky tomorrow
03 Jan The instrument is ON. Everything nominal. Shutter still closed, will be opened on Jan. 17.

2006
CoRoT launch campaign

28 Dec. Next events: ul>

  • 02 Jan. 07: switch on of electric volatage
  • 18 Jan. 07: opening of shutter; first light 27 Dec. Launch successful at 14h 23m 38.7s UT. A commissioning phase of 2 months begins. First scientific data gathering starts in March 2007.
    27 Dec. Fuelling has been authorized
    27 Dec. Expected launch count down (UT): 26 Dec. Soyuz with the CoRoT logo on the fairing on the launch pad
    26 Dec. Soyuz on the launch pad
    26 Dec. Clear sky in Baikonur. Everything nominal.
    24 Dec. The launcher and CoRoT have arrived at 06h (Moscow time) at the launch pad.
    22 Dec. Post launch events: 19 Dec. Next events: Transfer of upper stage to MIK-40 for final launcher assembly (Dec 19-20) - Transfer Readiness Review (Dec 23) - Transfer to launch pad (Dec 24) [from Thien Lam-Trong, Project Manager]
    18 Dec. The installation of the satellite in the fairing has begun. After completion, it will be transported on area 31 for assembling with the launcher "Soyuz-2b".
    15 Dec. CoRoT launch final preparation progressing well
    13 Dec. Successful fueling of the tanks of the Fregat upper stage.
    12 Dec. New images of CoRoT in Baikonur.
    05 Dec. Due to a defect on a hydrazine tank of Fregat, the new launch date is Dec. 27
    01 Dec. Launch at 14:43:17 UT (Dec. 21)
    28 Nov. CoRoT launch campaign website at CNES
    24 Nov. CoRoT in clean room in Baikonur
    18 Nov. Picture of Fregat, the last stage of the Soyuz launcher
    15 Nov. The CoRoT spacecraft has arrived in Baikonur
    27 Oct. Soyuz 2-1.b to be checked on November 6-10
    27 Oct. New launch date: 21-22 December with Soyuz 2-1.b from Baikonur (Kasakhstan)

    News

    CoRoT is a space mission approved by the French Space Agency CNES, with a participation of Austria, Belgium, Brazil, Germany, Spain, ESA and ESTEC.

    It is dedicated to stellar sismology and the the study of extrasolar planets.
    It is the first approved space mission dedicated to these subjects.

    The spacecraft consists of a ~ 30 cm telescope with an array of CCD's as detectors. It will monitor the lightcurves of well chosen stars.


    The present page is only about the extra-solar planets part of the mission.

    Other CoRoT web sites are at:

    1. The occultation method of detection of planets
      2.
      1. History of the photometric detection method

        2. The idea of the detection of planets by their transits was originally proposed by O. Struve (1952), incidentally in a paper on spectroscopy.
        It was then investigated quantitatively by Rosenblatt (1971) and revisited by Borucki et al. (1984, 1988) who proposed the idea of a dedicated space mission.
        It was subsequently proposed by Schneider (1988) and Schneider & Chevreton (1990) that a mission dedicated to stellar sismology could also search for planets by transits.
      2. Principles of the method; what can be learned about the planets
        3.
        The occultation method searches for planetary transits when the planet passes in front of its parent star. The main pertinent parameters are:
        1. The luminosity drop eta of the star :
          eta   =  (RPl/R*)2
        2. The geometric probability p of occultations
          p   =   R*/a
        3. The duration D of the transit
          D   =   (P/pi).(R*/a)
        where a is the orbital distance to the star and P the orbital period of the planet.

        The occultation method gives acces to:

        1. The orbital period, and thus the orbital distance to the star, of the planet
        2. The radius of the planet deduced from the luminosity drop during the transit
        3. The inclination i of the planetary orbit; this quantity becomes astrophysically interesting when compared to the equatorial plane of the parent star (deduced from its V.sin i and rotation period (Hale et. al. 1992).
      3. Advantages of the method

        1. The occultation method is one of the very few methods capable to detect Earth-sized planets in the Habitable Zone (HZ) of their parent star within the few next years.
          The HZ around a star is defined as the orbital distance at which the planet temperature allows for liquid water. This is of paramount importance for the search for Life in the Universe.
        2. It is a first step toward subsequent spectroscopic studies of the planet atmosphere (by absorption of the parent star's light) during the transit (Schneider 1994, Schneider & Doyle 1995, Coustenis et al. 1996)

    2. The CoRoT mission: extrasolar planets part

      3. The details of the payload are not entirely fixed. The incident beam after the main mirror is divided into two parts, one dedicated to sismology, the other to planetary transits.
      The planetary transits sector has two CCD's. The lightcurves of stars will be monitored in two colors. The overall potential of CoRoT is to detect several tens of Earth sized planets.

    3. References

      4. (for a more complete list, see the Extrasolar Planets Bibliography)

      1. BORUCKI, W. J., ALLEN L. E., TAYLOR W. S., YOUNG A. T. & SCHAEFER A. R., 1988
        A photometric approach to detecting earth-sized planets
        in Bioastronomy - The next steps; Proceedings of the Ninety-ninth IAU Colloquium, Balaton, Hungary, June 22-27, 1987, G. Marx (ed.), Kluwer
        abstract
      2. BORUCKI W. J. & SUMMERS A. L., 1984
        The photometric method of detecting other planetary systems
        Icarus, 58, 121
        abstract
      3. COUSTENIS A., SCHNEIDER J., BOCKELEE-MORVAN D., RAUER H., WITTEMBERG R., CHASSEFIERE E., GREENE T., PENNY A. & GUILLOT T., 1996
        Spectroscopy of 51 Peg B: Search for Atmospheric Signatures
        Planets Beyond the Solar System and the Next Generation of Space Missions
        Baltimore 16-18 October 1996
        abstract
      4. DELEUIL M., BARGE P., LEGER A. & SCHNEIDER J.,1996
        Detection of Earth-like Planets with the CoRoT Space Mission
        Planets Beyond the Solar System and the Next Generation of Space Mission, STScI, Baltimore 16 - 18 October 1996
        abstract
      5. HALE A. & DOYLE L., 1994
        The photometric method of extrasolar planets detection revisited
        Astr. & Spa. Sci., 212, 335
        abstract
      6. ROSENBLATT F. 1971
        A two-color photometric method for detection of extra-solar planetary systems
        Icarus, 14, 71
      7. SCHNEIDER J., 1996
        Photometric search for extrasolar planets
        Astr. & Spa. Sci., 241, 35
      8. SCHNEIDER J., 1994
        On the search for O2 in extrasolar planets.
        Astr. & Spa. Sci., 212, 321
        abstract
      9. SCHNEIDER J., 1988
        La recherche des planetes extrasolaires.
        in Journees d'exobiologie, CNES, 16 Nov. Raulin & Brack Eds. p. 93
      10. SCHNEIDER J. & CHEVRETON M., 1990
        The photometric search for earth-sized extrasolar planets by occultation in binary systems
        Astron. & Astrophys., 232, 251
        abstract
      11. SCHNEIDER J. & DOYLE L. R., 1995
        Ground-based detection of terrestrial extrasolar planets by photometry : the case for CM Draconis
        Earth, Moon & Planets, 71, 153
      12. STRUVE O., 1952
        The Observatory, 72, 199

    4. Other sites relevant to CoRoT