High Accuracy Radial Velocity Planet Searcher
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The High Accuracy Radial Velocity Planet Searcher (HARPS) is a high-precision echelle planet-finding spectrograph installed in 2002 on the ESO's 3.6m telescope at La Silla Observatory in Chile. The first light was achieved in February 2003. HARPS has discovered over 130 exoplanets to date, with the first one in 2004, making it the most successful planet finder behind the Kepler space telescope. It is a second-generation radial-velocity spectrograph, based on experience with the ELODIE and CORALIE instruments.
Characteristics
The HARPS can attain a precision of 0.97 m/s (3.5 km/h), making it one of only two instruments worldwide with such accuracy.[citation needed] This is due to a design in which the target star and a reference spectrum from a thorium lamp are observed simultaneously using two identical optic fibre feeds, and to careful attention to mechanical stability: the instrument sits in a vacuum vessel which is temperature-controlled to within 0.01 kelvins. The precision and sensitivity of the instrument is such that it incidentally produced the best available measurement of the thorium spectrum.[citation needed] Planet-detection is in some cases limited by the seismic pulsations of the star observed rather than by limitations of the instrument.
The principal investigator on the HARPS is Michel Mayor who, along with Didier Queloz and Stéphane Udry, have used the instrument to characterize the Gliese 581 planetary system, home to one of the smallest known exoplanets orbiting a normal star, and two super-Earths whose orbits lie in the star's habitable zone.
It was initially used for a survey of one-thousand stars.[citation needed]
Since October 2012 the HARPS spectrograph has the precision to detect a new category of planets: habitable super-Earths. This sensitivity was expected from simulations of stellar intrinsic signals, and actual observations of planetary systems. Currently, the HARPS can detect habitable super-Earth only around low-mass stars as these are more affected by gravitational tug from planets and have habitable zones close to the host star.
Discoveries
This is an incomplete list of exoplanets discovered by the HARPS. The list is sorted by the date of the discovery's announcement. As of December 2017, the list contains 134 exoplanets.
| HD 330075 b 10 February 2004 μ Arae c 25 August 2004 HD 2638 b 22 March 2005 HD 27894 b 22 March 2005 HD 63454 b 22 March 2005 HD 93083 b 30 March 2005 HD 101930 b 30 March 2005 Gliese 581 b 8 September 2005 HD 4308 b 12 October 2005 HD 212301 b 25 January 2006 HD 69830 b 18 May 2006 HD 69830 c 18 May 2006 HD 69830 d 18 May 2006 Mu Arae d 14/18 August 2006 Gliese 674 b 2 April 2007 HD 100777 b 6 April 2007 HD 190647 b 6 April 2007 HD 221287 b 6 April 2007 Gliese 581 c 23 April 2007 Gliese 581 d 23 April 2007 HD 171028 b 7 August 2007 HD 40307 b 27 June 2008 HD 40307 c 27 June 2008 HD 40307 d 27 June 2008 Gliese 176 b 4 September 2008 BD-17°63 b 26 October 2008 HD 20868 b 26 October 2008 HD 73267 b 26 October 2008 HD 131664 b 26 October 2008 HD 145377 b 26 October 2008 HD 153950 b 26 October 2008 HD 47186 b 9 December 2008 HD 47186 c 9 December 2008 HD 181433 b 9 December 2009 HD 181433 c 9 December 2009 HD 181433 d 9 December 2009 HD 45364 b 3 February 2009 HD 45364 c 3 February 2009 Gliese 581 e 21 April 2009 Gliese 667 Cb 19 October 2009 BD-08°2823 b 16 December 2009 BD-08°2823 c 16 December 2009 HD 5388 b 16 December 2009 HD 181720 b 16 December 2009 HD 190984 b 16 December 2009 | HD 125612 c 29 December 2009 HD 125612 d 29 December 2009 HD 215497 b 29 December 2009 HD 215497 c 29 December 2009 HIP 5158 b 29 December 2009 HD 85390 b 5 October 2010 HD 90156 b 5 October 2010 HD 103197 b 5 October 2010 HIP 12961 b 6 December 2010 HD 1690 b 17 December 2010 HD 25171 b 17 December 2010 HD 113538 b 17 December 2010 HD 113538 c 17 December 2010 HD 217786 b 17 December 2010 HD 33473 Ab 17 December 2010 HD 89839 b 17 December 2010 HD 167677 b 17 December 2010 HD 10180 b 23 November 2010 HD 10180 c 23 November 2010 HD 10180 d 23 November 2010 HD 10180 e 23 November 2010 HD 10180 f 23 November 2010 HD 10180 g 23 November 2010 HD 10180 h 23 November 2010 HD 63765 b 1 July 2011 HD 104067 b 1 July 2011 HD 125595 b 1 July 2011 HIP 70849 b 1 July 2011 HD 137388 b 8 July 2011 HD 204941 b 8 July 2011 HD 7199 b 8 July 2011 HD 7449 b 8 July 2011 82 G. Eridani b 17 August 2011 82 G. Eridani c 17 August 2011 82 G. Eridani d 17 August 2011 HD 85512 b 17 August 2011 HR 7722 c 17 August 2011 HD 1461 c 12 September 2011 HD 13808 b 12 September 2011 HD 13808 c 12 September 2011 HD 20003 b 12 September 2011 HD 20003 c 12 September 2011 HD 20781 b 12 September 2011 HD 20781 c 12 September 2011 HD 21693 b 12 September 2011 | HD 21693 c 12 September 2011 HD 31527 b 12 September 2011 HD 31527 c 12 September 2011 HD 31527 d 12 September 2011 HD 38858 b 12 September 2011 HD 39194 b 12 September 2011 HD 39194 c 12 September 2011 HD 39194 d 12 September 2011 HD 45184 b 12 September 2011 HD 51608 b 12 September 2011 HD 51608 c 12 September 2011 HD 93385 b 12 September 2011 HD 93385 c 12 September 2011 HD 96700 b 12 September 2011 HD 96700 c 12 September 2011 HD 126525 b 12 September 2011 HD 134060 b 12 September 2011 HD 134060 c 12 September 2011 HD 134606 b 12 September 2011 HD 134606 c 12 September 2011 HD 134606 d 12 September 2011 ν2 Lupi b 12 September 2011 ν2 Lupi c 12 September 2011 ν2 Lupi d 12 September 2011 HD 150433 b 12 September 2011 HD 154088 b 12 September 2011 HD 157172 b 12 September 2011 HD 189567 b 12 September 2011 HD 204313 c 12 September 2011 HD 215152 b 12 September 2011 HD 215152 c 12 September 2011 HD 215456 b 12 September 2011 HD 215456 c 12 September 2011 Gliese 667 Cc 21 November 2011 HD 10180 i 5 April 2012 HD 10180 j 5 April 2012 GJ 3470 b 22 June 2012 Gliese 676 c 29 June 2012 Gliese 676 d 29 June 2012 Gliese 676 e 29 June 2012 Gliese 163 b 6 September 2012 Gliese 163 c 6 September 2012 Gliese 667 Cd 25 June 2013 Gliese 667 Cg 25 June 2013 |
| HD 330075 b | 10 February 2004 | |
| μ Arae c | 25 August 2004 | |
| HD 2638 b | 22 March 2005 | |
| HD 27894 b | 22 March 2005 | |
| HD 63454 b | 22 March 2005 | |
| HD 93083 b | 30 March 2005 | |
| HD 101930 b | 30 March 2005 | |
| Gliese 581 b | 8 September 2005 | |
| HD 4308 b | 12 October 2005 | |
| HD 212301 b | 25 January 2006 | |
| HD 69830 b | 18 May 2006 | |
| HD 69830 c | 18 May 2006 | |
| HD 69830 d | 18 May 2006 | |
| Mu Arae d | 14/18 August 2006 | |
| Gliese 674 b | 2 April 2007 | |
| HD 100777 b | 6 April 2007 | |
| HD 190647 b | 6 April 2007 | |
| HD 221287 b | 6 April 2007 | |
| Gliese 581 c | 23 April 2007 | |
| Gliese 581 d | 23 April 2007 | |
| HD 171028 b | 7 August 2007 | |
| HD 40307 b | 27 June 2008 | |
| HD 40307 c | 27 June 2008 | |
| HD 40307 d | 27 June 2008 | |
| Gliese 176 b | 4 September 2008 | |
| BD-17°63 b | 26 October 2008 | |
| HD 20868 b | 26 October 2008 | |
| HD 73267 b | 26 October 2008 | |
| HD 131664 b | 26 October 2008 | |
| HD 145377 b | 26 October 2008 | |
| HD 153950 b | 26 October 2008 | |
| HD 47186 b | 9 December 2008 | |
| HD 47186 c | 9 December 2008 | |
| HD 181433 b | 9 December 2009 | |
| HD 181433 c | 9 December 2009 | |
| HD 181433 d | 9 December 2009 | |
| HD 45364 b | 3 February 2009 | |
| HD 45364 c | 3 February 2009 | |
| Gliese 581 e | 21 April 2009 | |
| Gliese 667 Cb | 19 October 2009 | |
| BD-08°2823 b | 16 December 2009 | |
| BD-08°2823 c | 16 December 2009 | |
| HD 5388 b | 16 December 2009 | |
| HD 181720 b | 16 December 2009 | |
| HD 190984 b | 16 December 2009 | |
| HD 125612 c | 29 December 2009 | |
| HD 125612 d | 29 December 2009 | |
| HD 215497 b | 29 December 2009 | |
| HD 215497 c | 29 December 2009 | |
| HIP 5158 b | 29 December 2009 | |
| HD 85390 b | 5 October 2010 | |
| HD 90156 b | 5 October 2010 | |
| HD 103197 b | 5 October 2010 | |
| HIP 12961 b | 6 December 2010 | |
| HD 1690 b | 17 December 2010 | |
| HD 25171 b | 17 December 2010 | |
| HD 113538 b | 17 December 2010 | |
| HD 113538 c | 17 December 2010 | |
| HD 217786 b | 17 December 2010 | |
| HD 33473 Ab | 17 December 2010 | |
| HD 89839 b | 17 December 2010 | |
| HD 167677 b | 17 December 2010 | |
| HD 10180 b | 23 November 2010 | |
| HD 10180 c | 23 November 2010 | |
| HD 10180 d | 23 November 2010 | |
| HD 10180 e | 23 November 2010 | |
| HD 10180 f | 23 November 2010 | |
| HD 10180 g | 23 November 2010 | |
| HD 10180 h | 23 November 2010 | |
| HD 63765 b | 1 July 2011 | |
| HD 104067 b | 1 July 2011 | |
| HD 125595 b | 1 July 2011 | |
| HIP 70849 b | 1 July 2011 | |
| HD 137388 b | 8 July 2011 | |
| HD 204941 b | 8 July 2011 | |
| HD 7199 b | 8 July 2011 | |
| HD 7449 b | 8 July 2011 | |
| 82 G. Eridani b | 17 August 2011 | |
| 82 G. Eridani c | 17 August 2011 | |
| 82 G. Eridani d | 17 August 2011 | |
| HD 85512 b | 17 August 2011 | |
| HR 7722 c | 17 August 2011 | |
| HD 1461 c | 12 September 2011 | |
| HD 13808 b | 12 September 2011 | |
| HD 13808 c | 12 September 2011 | |
| HD 20003 b | 12 September 2011 | |
| HD 20003 c | 12 September 2011 | |
| HD 20781 b | 12 September 2011 | |
| HD 20781 c | 12 September 2011 | |
| HD 21693 b | 12 September 2011 | |
| HD 21693 c | 12 September 2011 | |
| HD 31527 b | 12 September 2011 | |
| HD 31527 c | 12 September 2011 | |
| HD 31527 d | 12 September 2011 | |
| HD 38858 b | 12 September 2011 | |
| HD 39194 b | 12 September 2011 | |
| HD 39194 c | 12 September 2011 | |
| HD 39194 d | 12 September 2011 | |
| HD 45184 b | 12 September 2011 | |
| HD 51608 b | 12 September 2011 | |
| HD 51608 c | 12 September 2011 | |
| HD 93385 b | 12 September 2011 | |
| HD 93385 c | 12 September 2011 | |
| HD 96700 b | 12 September 2011 | |
| HD 96700 c | 12 September 2011 | |
| HD 126525 b | 12 September 2011 | |
| HD 134060 b | 12 September 2011 | |
| HD 134060 c | 12 September 2011 | |
| HD 134606 b | 12 September 2011 | |
| HD 134606 c | 12 September 2011 | |
| HD 134606 d | 12 September 2011 | |
| ν2 Lupi b | 12 September 2011 | |
| ν2 Lupi c | 12 September 2011 | |
| ν2 Lupi d | 12 September 2011 | |
| HD 150433 b | 12 September 2011 | |
| HD 154088 b | 12 September 2011 | |
| HD 157172 b | 12 September 2011 | |
| HD 189567 b | 12 September 2011 | |
| HD 204313 c | 12 September 2011 | |
| HD 215152 b | 12 September 2011 | |
| HD 215152 c | 12 September 2011 | |
| HD 215456 b | 12 September 2011 | |
| HD 215456 c | 12 September 2011 | |
| Gliese 667 Cc | 21 November 2011 | |
| HD 10180 i | 5 April 2012 | |
| HD 10180 j | 5 April 2012 | |
| GJ 3470 b | 22 June 2012 | |
| Gliese 676 c | 29 June 2012 | |
| Gliese 676 d | 29 June 2012 | |
| Gliese 676 e | 29 June 2012 | |
| Gliese 163 b | 6 September 2012 | |
| Gliese 163 c | 6 September 2012 | |
| Gliese 667 Cd | 25 June 2013 | |
| Gliese 667 Cg | 25 June 2013 |
Gallery
- HELIOS instrument installed to feed sunlight via fibre optics to the HARPS
- A decade of discoveries from HARPS
- HARPS spectrograph
- HARPS spectrograph detail
- Animation of HD 10180 with its seven planets
See also

Similar instruments:
- HARPS-N is a copy of this instrument installed in the northern hemisphere in 2012.
- HARPS3 is an updated design of this instrument that will be installed on an upgraded and roboticised Isaac Newton Telescope, in 2024.
- Fiber-optic Improved Next-generation Doppler Search for Exo-Earths, operating at Lick observatory since 2009
- Anglo-Australian Planet Search or AAPS is another southern hemisphere planet search program.
- ESPRESSO is a new-generation spectrograph for ESO's VLT.
- Automated Planet Finder, at the Lick observatory, commissioned in 2013.
- CAFE (Calar Alto Fibre-fed Echelle spectrograph) installed on the Calar Alto Observatory's 2.2-metre telescope in 2014, and the CARMENES mounted on the 3.5-metre telescope in 2016.
- EXPRES is a third generation radial velocity spectrograph that is planned to be installed on the Lowell Discovery Telescope.
Space based detectors :
- CoRoT, spacecraft operating since 2007
- Kepler space telescope, operational until 2018
- Terrestrial Planet Finder, cancelled
- Space Interferometry Mission, construction halted in 2010
- Darwin, early studies for a multi-satellite mission