Geneva Observatory Web Page Geneva Planet Search Porgrammes

Extrasolar Planets: The Chronology of the Discoveries

Last Update: May 25th, 2007, (D.Naef)


  • May 23rd, 2007 Detection of a planetary system around the metal-poor star HD 155358. See Cochran et al. (2007, astro-ph/0705.3228).

  • May the 15th 2007 Detection of the first transiting Neptune-mass planet. Transits of GJ 436 b are reported by Gillon et al. (2007, astro-ph/0705.2219).

  • May the 14th 2007 Detection of the astrometric signature induced by HD 33636 b by Bean et al. using HST-FGS data. The orbital inclination is low (4 degrees) and the true mass of this companion is in the stellar range: 140 M_Jup (M6V star). See Bean et al. 2007 for details: astro-ph/0705.1861.

  • May the 14th 2007 TrES-3b: a massive short-period transiting planet announced by O'Donovan et al. (2007, astro-ph/0705.2004).

  • May the 7th 2007 Niedzielski et al. announce the detection of a planetary companion to the K Giant HD 17092 (see astro-ph/0705.0935).

  • May 3, 2007 CoRoT-Exo-1b: first transiting planet detected with the CoRoT satellite

  • May 1, 2007 2 transiting planets announced: XO-2b (Burke et al. 2007, astro-ph/0705.0003) and HAT-P-2b (Bakos et al. 2007, astro-ph/0705.0126).

  • April the 25th 2007 Gl 581 c, a 5 Earth-mass habitable planet, and Gl 581 d a 8 Earth-mass planet detected with HARPS. See Udry et al. 2007, A&A submitted. See also ESO Press Release 22/07.

  • April the 10th 2007 5 planets around metal-rich stars announced by Fischer et al.: HD 11506 b, HD 17156 b, HD 125612 b, HD 170469 b and HD 231701 b (2007, ApJ in press, astro-ph/0704.1191)

  • April the 3rd 2007 HD 70573 b, a planet around a young star announced by Setiawan et al. (2007, ApJL submitted, astro-ph/0704.0441).

  • March the 27th 2007 Doellinger et al. (2007, A&A in press, astro-ph/0703672) announce the detection of a planet orbiting the giant star 4 UMa.

  • March the 6th 2007 The detection of a 11 Earth-mass planet around the low-mass star GJ 674 is announced by Bonfils et al. (2007, A&A in press, astro-ph/0704.0270).

  • March the 5th 2007 The detection of the 3 planets HD 100777 b, HD 190647 b and HD 221287 b is announced by Naef et al. (2007, A&A in press, astro-ph/0704.0917).

  • February the 18th 2007 The detection of a Neptune mass planet around the metal-rich star HD 219828 is announced by Melo et al. (2007, A&A in press, astro-ph/0702459). These authors also confirm and improve the orbital solution for HD 102195 b (announced in 2006 by Ge et al., see ApJ 648, 683)

  • February the 9th 2007 The detection of HD 23127 b and HD 159868 b is announced by the AAT planet serach team. See O'Toole et al. (2007, ApJ in press).

  • February the 7th 2007 Detection of the first planetary companion to an open-cluster star. A 7.6 M_Jup planet orbiting the Hyades giant eps Tau detected by Sato et al. (2007, ApJL in press).


  • November the 21st 2006 4 new planets (3 in systems), HIP 14810 b&c, HD 154345 b and HD 187123 c, announced by Wright et al. (2007, ApJ 653, 533).

  • October the 27th 2006 Updated planet parameters for OGLE-TR-10 b and OGLE-TR-56-b obtained from VLT-FORS1 high-precision photometric data. See Pont et al. (2007, A&A 465, 1069).

  • October the 17th 2006 Usp And b (HD9826 b) Night versus Day thermal emission variation detected with Spitzer. See Harrington et al. (2006, Science 314, 623)

  • October the 9th 2006 Astrometric signal of Espilon Eridani b detected by Benedict et al. (2006). See AJ 132, 2206

  • October the 6th 2006 The detection of a Jupiter-mass planet around the nearby M3.5V dwarf GJ 849 reported by Butler et al. (2006, PASP 118, 1685)

  • September the 25th 2006 WASP-1b and WASP-2b: 2 transiting extra-solar planets detected by the superWASP project team. See Collier-Cameron et al. (2007, MNRAS 375, 951).

  • September the 13th 2006 HAT-P-1 b: first transiting exoplanet detected by the HATNet project team. See Bakos et al. (2007, ApJ 656, 552).

  • September the 12th 2006 The Trans-atlantic Exoplanet Survey reports the detection of a new transiting planet: TrES-2 b. See O'Donnovan et al. 2006, (ApJ 615, L61)

  • August the 14th 2006 4th planet around mu Ara also reported by Gozdiewski et al. (2007, ApJ 657, 546).

  • August the 5th 2006 Updated orbit for mu Ara (HD 169830) published in Pepe et al. (2007, A&A 462, 769). A 4th planet is detected and the orbit of massive outer planet is well constrained for the first time.

  • July the 21st 2006 A Catalog of nearby exoplanets published in Butler et al. 2006 (ApJ 646, 505). 5 new extra-solar planets announced in the same paper: HD 11964 b, HD 66428 b, HD 99109 b, HD 107148 b and HD 164922 b.

  • June the 21st 2006 The presence of a planet around Beta Gem confirmed. See Hatzes et al. 2006, (A&A 457, 335)

  • May the 17th 2006 XO-1 b: a transiting planet announced by the eXOplanet project team. See McCullough et al. 2006, (ApJ 648, 1228)

  • May the 17th 2006 HD 69830: a system with 3 Netpune-mass planets. See Lovis et al. 2006, (Nature 441, 305) and ESO Press release 18-06

  • April the 17th 2006 3 short-period planets announced by the N2K consortium: HD 33283 b, HD 86081 b and HD 224693 b. See Johnson et al. 2006, (ApJ 647, 600)

  • March the 14th 2006 HD 187085 b and HD 20782 b: 2 eccentric exoplanet detected by the AAT team. See Jones et al. 2006, (MNRAS 369, 249)

  • March the 10th 2006 OGLE-2005-BLG-169 b: a 13 Earth mass planet candidate discovered by microlensing. See Gould et al. 2006, (ApJ 644, L37)

  • February the 25th 2006 Second planet on a 2:1 resonance around HD 73526 detected by the AAT team. See Tinney et al. 2006, (ApJ 647, 594)

  • February the 20th 2006 Infrared emission of HD189733b detected with Spitzer by Deming et al. (ApJ 644, 560)

  • January the 25th 2006 OGLE-2005-BLG-390Lb: a 5.5 Earth-mass planet discovered through microlensing. See J.-P. Beaulieu's Nature paper: Nature 439, 437

  • January the 13th 2006 HD 102195 b detected with the Exoplanet Tracker. See Ge et al. 2006, (ApJ 648, 683)


  • November the 24th 2005 A massive planet to the young disc star HD 81040 is announced by the CfA - Geneva - Tel-Aviv collaboration. This discovery is based on KECK/HIRES and OHP/ELODIE radial-velocity data and is published in Sozzetti et al. 2005, A&A in press.

  • October the 6th 2005 Detection of a planet transiting the bright K star HD 189733 with ELODIE and photometric data taken with the 1.2-m Telescope at OHP (see Bouchy et al. 2005, A&A submitted).

  • September the 6th 2005 HD 33564 b: a massive planet orbiting a F6V star detected with ELODIE (see Galland et al. 2005, A&A in press).

  • August the 22th 2005 Several planets announced during the OHP colloquium "The tenth anniversary of 51 Peg b": HD 109749 and HD 149143 detected by the N2K Consortium (see Fischer et al. 2005, ApJ in press), HD4308 b (see Udry et al. 2005, A&A in press), HD 212301 b and (see Lo Curto et al. 2005, A&A submitted) Gl 581 b (see Bonfils et al. 2005, A&A in press) detected with HARPS and HD 118203 b detected with ELODIE (see Da Silva et al. 2005, A&A in press, also containing a confirmation of HD 149143 b)

  • August the 4th 2005 HD 188753 b: a planet in a triple system detected by Konacki (2005, Nature 436, 230, ADS)

  • July the 1st 2005 Detection of HD 149026 b, a short-period transiting Saturn mass planet by the N2K consortium. The presence of a large dense planetary core is inferred from the data. See Sato et al., ApJ in press (astro-ph/0507009)

  • June the 24th 2005 Additional planets found around HD 37124 (3rd planet in the system), HD 108874 (2nd planet in the system), HD 128311 (2nd planet in the system) and GJ 777 A (confirmation of the long period planet + detection of a very low-mass short-period companion) by Vogt et al. (ApJ in press). A linear systemic velocity drift is also detected for HD 50499 revealing the presence of another not yet characterized body in the system. Vogt et al. also show that HD 217107 c, although not well constrained, is most probably also a planetary companion.

  • June the 13th 2005 The third planetary companion to GJ 876 announed by Rivera et al. 2005, submitted to ApJ. GJ 876 d is the lightest extra-solar planet known so far (mass between 6 and 8 Earth masses).

  • May the 26th 2005 A planetary companion detected around the giant star HD 11977 using ESO-FEROS. See Setiawan et al. 2005, submitted to A&A (astro-ph/0505510)

  • May the 24th 2005 OGLE-2005-BLG-071: a planetary microlensing event. See Udalski et al. 2005, submitted to ApJL (astro-ph/0505451)

  • April the 9th 2005 A low-mass companion to HD 8673 detected by the TOPS (Tautenburg Observatory Planet Search) team.

  • April the 5th 2005 A low-mass companion (planet or brown dwarf) to the giant star HD 13189 detected by Tautenburg, McDonald and Hobby-Heberly Telescope teams.

  • March the 27th 2005 Direct detection of a very low-mass companion (planet or brown dwarf) to the young star GQ Lup with VLT-NACO. See Neuhäuser et al. 2005, A&A 435, L13 and ESO press release

  • March the 22nd 2005 Thermal emission of HD 209458 b and TrES-1b detected with the Spitzer Space Telescope. See Deming et al. 2005, Nature 434, 740 and Charbonneau et al. 2005, ApJ (in press)

  • February the 8th 2005 7 planets discovered with HARPS and/or CORALIE announced during the Aspen Winter Conference 2005 "Planet Formation and Detection": HD 2638 b, HD 27894 b, HD 63454 b, HD 93083 b, HD 101930 b, HD 102117 b, HD 142022 Ab. See Moutou et al. 2005, A&A in press and Lovis et al. 2005, A&A in press (astro-ph/0503660)

  • January the 20th 2005 5 planets detected with HIRES at the Keck published: HD 45350 b, HD 99492 b, HD 117207 b, HD 183263 b, HD 188015 b. See Marcy et al. 2005, ApJ 619, 570


  • November the 17th 2004 The presence of HD 202206 c, a 2.4 M_Jup planet, reported by Correia et al. (astro-ph/0411512). HD 202206 was already known to host a 17.5 M_Jup companion (see Udry et al. 2002, A&A 390, 267)

  • October the 15th 2004 A possible planet around OGLE-TR-10. See Bouchy et al. 2004 for details.

  • September the 15th 2004 HD 154857 b detected by the AAT team (evidence of an additional signal is also reported).

  • September the 10th 2004 Possible first direct detection of an exoplanet with VLT/NAOS adaptive optics imaging facility: 2M1207 b. "A Giant Planet Candidate near a Young Brown Dwarf" by Chauvin et al (see also: ESO Press Release)

  • September the 7th 2004 Detection of HD 88133 b by the N2K consortium (Keck, Magellan + Subaru). See Fischer et al. for details (astro-ph/0409107)

  • August the 31st 2004 Detection of two very low-mass planets: 55 Cancri e the fourth planet in this system by McArthur et al. using HRS on the Hobby-Eberly Telescope and GJ 436 b by Butler et al. using HIRES on the Keck Telescope. The astrometric signal of 55 Cancri d also detected by McArthur et al. with the FGS on the Hubble Space Telescope.

  • August the 26th 2004 Detection of the radial-velocity signal induced by OGLE-TR-111 b using UVES/FLAMES on the VLT (see Pont et al. 2004).

  • August the 25th 2004 TrES-1b: A new transiting exoplanet detected by the Trans-Atlantic Exoplanet Survey (TreS) team . (see Boulder Press release or Alonso et al.)

  • August the 25th 2004 HD 160691 c : A 14 Earth-mass planet detected with HARPS (see ESO Press Release or Santos et al.)

  • July the 8th 2004 HD 37605 b: The first extra-solar planet detected with HRS on the Hobby-Eberly Telescope (Cochran et al.)

  • May the 3rd 2004 HD 219452 Bb withdrawn by Desidera et al.

  • April the 28th 2004 Orbital solution for OGLE-TR-113 confirmed by Konacki et al

  • April the 15th 2004 OGLE 2003-BLG-235/MOA 2003-BLG-53: a planetary microlensing event (Bond et al.)

  • April the 14th 2004 FLAMES-UVES spectroscopic orbits for two OGLE III transiting candidates: OGLE-TR-113 and OGLE-TR-132 (Bouchy et al.)

  • February 2004 Detection of Carbon and Oxygen in the evaporating atmosphere of HD 209458 b by A. Vidal-Madjar et al. (from HST observations).

  • January the 5th 2004 Two planets orbiting giant stars announced by Mitchell et al. during the AAS meeting: HD 59686 b and 91 Aqr b (HD 219499 b). Two other more massive companions, Tau Gem b (HD 54719 b) and nu Oph b (HD 163917 b), have also been announced by the same authors.


  • December 2003 First planet detected with HARPS: HD 330075 b (see Mayor et al., in the ESO Messenger No 114)

  • July the 3rd 2003 A long-period planet on a circular orbit around HD 70642 announced by the AAT team (Carter et al. 2003, ApJ 593, L43)

  • June the 30th 2003 7 new planets detected with CORALIE announced during the XIXth IAP colloquium in Paris: HD 10647 b, HD 41004 Ab,HD 65216 b, HD 111232 b, HD 142415 b, HD 169830 c, HD 216770 b

  • June the 26th 2003 The first planet detected with the HIgh Dispersion Echelle Spectrograph (HIDES) at the Okayama Astrophysical Observatory: HD 104985 b, a massive planet around a giant star (Sato et al. 2003, ApJ 597, L157).

  • May 2003 HD 192263 b is back (Santos et al., 2003 A&A 406, 373)!

  • April the 14th 2003 A 2.55-d planet around HD 73256 announced by the CORALIE team (Udry et al. A&A 407, 679)

  • March the 12th 2003 Detection of a cometary tail around HD 209458 b (Vidal-Madjar et al. 2003, Nature 422, 143)

  • March the 3rd 2003 OGLE-3: a possible transiting very short period planet

  • January the 22th 2003 A planetary companion to the giant star HD 47536 (ESO-Feros & CORALIE radial velocities, Setiawan et al. 2003, A&A 398 L19). ESO Press release

  • January the 16th 2003 HD 3651 b announced by Fischer et al. (Keck & Lick radial velocities)

  • January the 7th 2003 A transiting 1.2-day planet announced by the OGLE team


  • November the 29th 2002 the first SARG Exo-planet search planetary candidate around HD 219542 b

  • October the 7th 2002 HD 13507 b and HD 223084 b are in fact not planetary companions. The latest ELODIE and CORALIE measurements show that they are more massive (click here for details)

  • September the 24th 2002 a planetary companion orbiting gamma Cephei announced by A. Hatzes et al. The detection is based on radial-velocity measurements taken at McDonald Observatory.

  • September the 23th 2002 HD 216435 b announced by the Anglo-Australian Telescope Planet Search Team.

  • July the 8th 2002 HD 76700 b announced by the Anglo-Australian Telescope Planet Search Team.

  • July the 1st 2002 a planetary companions orbiting HD 2039 announced by the Anglo-Australian Telescope Planet Search Team.

  • June the 20th 2002 13 new Planetary Transit Candidates announced by the OGLE III Team.

  • June the 19th 2002Detections announced by the CORALIE Team: planetary companions to HD 114386, HD 147513 and HD 223084 (planet in binary); Independant discoveries of HD 196050 b and HD 216437 b.

  • June the 19th 2002 Detections announced by the ELODIE Team: planets around HD 13507 (planet in binary), HD 20367, HD 23596 and HD 150706; a Jupiter analog in orbit around Gl 777A (aka HD 190360A), in collaboration with the AFOE team; Independant discovery of HD 33636 b and HD 37124 c.

  • June the 13th 2002: New detections announced by the Anglo-Australian Telescope Planet Search Team: planets around HD 30177, HD 73526, HD 196050 and HD 216437.

  • June the 13th 2002: New detections announced by the California Planet Search Team: 2 new planets (including a Jupiter analog) orbiting 55 Cancri; the second planetary companion to HD 12661, HD 37124 and HD 38529; planetary companions to HD 49674 (36 Earth-mass, the lightest one to date), HD 72659, HD 108874, HD 114729 and HD 128311.

  • February the 21st 2002:Possible Planetary Transit Candidates announced by the OGLE Team

  • February the 7th 2002:A 12 Jupiter-mass companion to HD 136118 announced by Fischer et al. and confirmation of the orbital solutions for HD 50554 and HD 106252.

  • January the 8th 2002:A planet around the giant star iota Draconis detected by the California Planet Search Team


  • November the 27th 2001: Detection of Sodium in the atmosphere of the planet orbiting HD 209458 by Dave Charbonneau et al. using Hubble Space Telescope data

  • October the 15th 2001: 8 new planets announced: 5 with HIRES velocities (HD 4203, HD 4208, HD 33636, HD 68988 and HD 114783) and 3 from the AAT (HD 142, HD 23079 and HD 39091)

  • August the 15th 2001: 47 UMa c is announced by Geoff Marcy's Team

  • April the 4th 2001: 11 New Planets announced by the CORALIE, ELODIE & G Dwarf Planet Search Teams: HD 28185 b, HD 82943 b & c, HD 141937 b, HD 213240 b, HD 8574 b, HD 74156 b & c, HD 106252 b, HD 80606 b and HD 178911 Bb
  • January the 11th 2001: A Second Planet Around Gl 876 announced by Marcy's Team


  • November the 20th 2000: Planetary Candidates around HD 179949, HD 27442 and HD 160691 announced by the Anglo-Australian Observatory team

  • August the 7th 2000: 7 Low-Mass Companions (6 Planets, 1 Brown Dwarf) announced by the CORALIE & ELODIE Teams: HD 6434 b, HD 19994 b, HD 83443 c, HD 92788 b (independant discovery), HD 121504 b , HD 168443 c, HD 190228 b
  • July the 24th 2000: The Planetary Companions to HD 38529 and HD 92788 announced by Fischer et al.

  • May the 4th 2000: 8 Low-Mass Companions (6 Planets, 2 Brown Dwarfs) announced by the CORALIE Team: HD 52265 b (Independant discovery), HD 82943 b, HD 83443 b, HD 108147 b, HD 162020 b, hd 168746 b, HD 169830 b, HD 202206 b
  • April the 27th 2000: Planets orbiting BD -10 3166 and HD 52265 announced by Butler et al.

  • March the 29th 2000: Sub-Saturnian Mass Planet Around HD 16141 and HD 46375 announced by Marcy et al.

  • February the 14th 2000: The SFSU Team announces the Detection of a Planet Around HD 12661

  • February the 8th 2000: A Planet Around HD 89744 is Detected by the AFOE Team

  • January the 25th 2000: The CORALIE Team annonces the Detection of a planetary companion in orbit around GJ 3021


  • November the 15th 1999: Planets Around HD 37124, HD 177830, HD 134987, HD 222582 and HD 10697 announced by Marcy et al.

  • November the 15th 1999: HD 209458: A Transiting Hot Jupiter

  • September the 28th 1999: The fourth CORALIE Planetary Candidate: HD 192263 b (Independant discovery by Marcy's team)
  • September the 4th 1999: The third CORALIE Planetary Candidate: HD 130322 b
  • July the 29th 1999: The Companion to iota Hor is announced by the ESO-CES Team
  • April the 15th 1999: 2 New planets orbiting Ups And: The First Extrasolar Planetary Sytem announced by Marcy's Team in collaboration with the AFOE Team

  • February 1999: The Second CORALIE Planetary Candidate: HD 75289 b


  • November the 24th 1998: The First CORALIE Planetary Candidate: Gl 86 b
  • October the 14th: A Planet Around HD 168443 is announced by Marcy et al.

  • October the 12th: Planets Around HD 195019 and HD 217107 detected by Fischer et al.

  • September the 22th 1998: The Planetary Companion to HD 210277 is announced by Marcy et al.

  • September the 24th 1998: The Short-Period Companion to HD 187123 is announced by Butler et al.

  • July 1998: A Planet Around 14 Herculis: the Third ELODIE Planetary Candidate

  • June 1998: A Planet Around Gl 876: The Second ELODIE Planetary Candidate (Independant discovery by G. Marcy's team)


  • April 1997: The Companion to rho Crb: the First detection of the AFOE Team


  • November 1996:The Companion to 16 CygB is announced by the McDonald Obseratory Team in collaboration with Geoff Marcy's Team

  • August 1996: Planetary Companions to 55 Cnc, Tau Boo and Ups And announced by the Geoff Marcy's Team

  • February 1996: The Companion to 47 UMa is announced by Geoff Marcy's Team

  • January 1996: The Companion to 70 Vir is announced by Geoff Marcy's Team


  • October the 12th 1995: Marcy and Butler start a radial-velocity follow-up of 51 Peg with the Hamilton Spectrograph at Lick Observatory. These measurement rapidly confirm the presence of the 0.5 Jupiter-Mass planet around this Star

  • October the 5th 1995: The first Extrasolar Planet, detected in Orbit around 51 Pegasi with the ELODIE echelle Spectrograph, is announced by Michel Mayor & Didier Queloz during the 9th Cambridge Workshop on Cool Stars, Stellar Systems and the Sun in Florence, Italy