List of exoplanets discovered before 2000

This is a list of exoplanets discovered before 2000. ^[1]

For exoplanets detected only by radial velocity, the mass value is actually a lower limit. (See Minimum mass for more information.)

While the existence of a substellar companion to Gamma Cephei was suspected since 1988, ^[2] the planet Gamma Cephei Ab was not confirmed until 2003, ^[3] and that is listed as its discovery year in exoplanet databases. Thus, this planet is in the List of exoplanets discovered between 2000–2009.

Name	Mass (MJ)	Radius (RJ)	Period (days)	Semi-major axis (AU)	Temp. (K)	Discovery method	Disc. Year	Distance (ly)	Host star mass (M☉)	Host star temp. (K)	Remarks
16 Cygni Bb	2.38		799.5	1.66		radial vel.	1996	68.99	1.04	5750
23 Librae b	1.61		258.18	0.81		radial vel.	1999	85.46	1.07	5736
47 Ursae Majoris b	2.53		1078	2.1		radial vel.	1996	45.02	1.08	5892	Proper name Taphao Thong
51 Pegasi b	0.46		4.230785	0.0527		radial vel.	1995	50.45	1.12	5793	Proper name Dimidium. First exoplanet discovered orbiting a main sequence star.
55 Cancri b	0.8306		14.65152	0.115227	700	radial vel.	1996	41.06	0.905	5196	Proper name Galileo
70 Virginis b	7.49		116.688	0.481		radial vel.	1996	58.42	1.09	5495
109 Piscium b	6.383		1075.69	2.14		radial vel.	1999	108.1	1.11	5600
Gliese 86 b	4.42		15.76491	0.11		radial vel.	1999	35.18	0.83	5182
Gliese 876 b	2.2756		61.1166	0.208317		radial vel.	1998	15.25	0.32	3129
HD 75289 b	0.49		3.50927	0.05	1260	radial vel.	1999	95.05	1.29	6117
HD 89744 b	8.35		256.78	0.917		radial vel.	1999	126.2	1.86	6291
HD 130322 b	1.15		10.70871	0.0925	720	radial vel.	1999	104.1	0.92	5387	Proper name Eiger
HD 168443 b	7.659		58.11247	0.2931		radial vel.	1998	129.4	0.995	5491
HD 177830 b	1.69		410.1	1.14		radial vel.	1999	205.1	1.70	4901
HD 187123 b	0.523		3.0965828	0.0426		radial vel.	1998	150.1	1.0	5830
HD 192263 b	0.56		24.3556	0.15	486	radial vel.	1999	64.08	0.66	4976	Proper name Beirut
HD 195019 b	3.98		18.20132	0.14		radial vel.	1998	123	1.21	5751
HD 209458 b	0.73	1.39	3.52474859	0.04707	1459	radial vel.	1999	157.8	1.23	6091	Informally named Osiris
HD 210277 b	1.29		442.19	1.13		radial vel.	1998	69.51	1.01	5538
HD 217107 b	1.30		7.12682	0.08		radial vel.	1998	65.47	1.00	5622
HD 222582 b	8.37	~1.12	572.38	1.34		radial vel.	1999	137.7	1.12	5790
Iota Horologii b	2.27		302.8	0.92		radial vel.	1999	56.51	1.25 [4]	6167
PSR B1257+12 b	0.000063		25.262	0.19		timing	1994	~2000	1.4		Proper name Draugr. Least massive exoplanet known.
PSR B1257+12 c	0.014		66.5419	0.36		timing	1992	~2000	1.4		Proper name Poltergeist
PSR B1257+12 d	0.012	0.13	98.2114	0.46		timing	1992	~2000	1.4		Proper name Phobetor
PSR B1620-26 b	2.5			23.0		timing	1993	12400	1.35
Rho Coronae Borealis b	1.045		39.8458	0.2196	614	radial vel.	1997	57.0	0.889	5627
Tau Boötis b	5.95		3.3124568	0.049		radial vel.	1996	51.07	1.34	6400
Upsilon Andromedae b	0.6876	~1.8	4.617033	0.059222		radial vel.	1996	43.74	1.3	6183	Proper name Saffar
Upsilon Andromedae c	1.981		241.258	0.827774		radial vel.	1999	43.74	1.3	6183	Proper name Samh
Upsilon Andromedae d	4.132	~1.02	1276.46	2.51329		radial vel.	1999	43.74	1.3	6183	Proper name Majriti

Bodies previously considered as candidates

HD 114762 b was once considered as the first discovered exoplanet. Found in 1989 by a team led by David Latham, it is now known to be a red dwarf star. ^[5] In 1991 it was reported an exoplanet 10 times the mass of Earth was discovered around the pulsar, PSR B1829-10. ^[6] It was subsequently retracted later in 1992.

Specific exoplanet lists

Lists of exoplanets

• List of directly imaged exoplanets
• List of exoplanet extremes
• List of exoplanet firsts
• List of exoplanets discovered by the Kepler space telescope
• List of exoplanets observed during Kepler's K2 mission
• List of extrasolar candidates for liquid water
• List of terrestrial exoplanet candidates for atmosphere detection
• List of hottest exoplanets
• List of coolest exoplanets
• List of multiplanetary systems
• List of circumbinary planets
• List of nearest exoplanets
• List of nearest terrestrial exoplanet candidates
• List of potentially habitable exoplanets
• List of proper names of exoplanets
• List of largest exoplanets
• List of smallest exoplanets
• List of transiting exoplanets
• List of exoplanets and planetary debris around white dwarfs
• List of extrasolar planetary collisions

Lists of exoplanets by year of discovery

• List of exoplanets discovered before 2000 (31)
• List of exoplanets discovered between 2000–2009 (375)
• List of exoplanets discovered in 2010 (109)
• List of exoplanets discovered in 2011 (179)
• List of exoplanets discovered in 2012 (149)
• List of exoplanets discovered in 2013 (149)
• List of exoplanets discovered in 2014 (869)
• List of exoplanets discovered in 2015 (144)
• List of exoplanets discovered in 2016 (1498)
• List of exoplanets discovered in 2017 (152)
• List of exoplanets discovered in 2018 (300)
• List of exoplanets discovered in 2019 (170)
• List of exoplanets discovered in 2020 (247)
• List of exoplanets discovered in 2021 (254)
• List of exoplanets discovered in 2022 (313)
• List of exoplanets discovered in 2023 (307)
• List of exoplanets discovered in 2024 (285)
• List of exoplanets discovered in 2025 (106)

References

1. "NASA Exoplanet Archive" . Retrieved 20 December 2019.
2. Campbell, Bruce; Walker, G. A. H.; Yang, S. (1988). "A Search for Substellar Companions to Solar-type Stars". The Astrophysical Journal. 331: 902. Bibcode:1988ApJ...331..902C. doi: 10.1086/166608 .
3. Hatzes, Artie P.; et al. (2003). "A Planetary Companion to Gamma Cephei A". The Astrophysical Journal. 599 (2): 1383–1394. arXiv: astro-ph/0305110 . Bibcode:2003ApJ...599.1383H. doi:10.1086/379281. S2CID   11506537.
4. "The planet-host star Iota Horologii".
5. Kiefer, Flavien (17 October 2019). "Determining the mass of the planetary candidate HD 114762 b using Gaia". Astronomy & Astrophysics. 632: L9. arXiv: 1910.07835 . Bibcode:2019A&A...632L...9K. doi:10.1051/0004-6361/201936942. S2CID   204743831.
6. Dieguez, Flávio. "Terra à vista". Superinteressante (in Portuguese). Archived from the original on 2008-05-15. Retrieved 2008-07-03.