List of exoplanet firsts

This is a list of exoplanet discoveries that were the first by several criteria, including:

and others.

The first

The choice of "first" depends on definition and confirmation, as below. The three systems detected prior to 1994 each have a drawback, with Gamma Cephei Ab being unconfirmed until 2002; while the PSR B1257+12 planets orbit a pulsar. This leaves 51 Pegasi b as the first confirmed exoplanet around a non-compact star.

First	Planet	Star	Year	Notes
First detected exoplanet later confirmed	Gamma Cephei Ab	Gamma Cephei	1988, 2002	First evidence for exoplanet to receive later confirmation.
First exoplanets to be confirmed	PSR B1257+12 B PSR B1257+12 C	PSR B1257+12	1992	First super-Earths. These exoplanets orbit a pulsar.
First confirmed exoplanet around non-compact star	51 Pegasi b	51 Pegasi	1995	First convincing exoplanet discovered around a Sun-like star. While the minimum mass of HD 114762 b was high enough that it could be a brown dwarf, 51 Peg b's minimum mass meant that it almost certainly was near the mass of Jupiter.

By detection method

Some of these planets had already been discovered by another method but were the first to be detected by the listed method.

Detection method	Planet	Star	Year	Notes
First planet detected via radial velocity	Gamma Cephei Ab	Gamma Cephei	1988	First evidence for exoplanet to receive later confirmation.
First planet detected via pulsar timing	PSR B1257+12 B PSR B1257+12 C	PSR B1257+12	1992
First planet detected by transit method	HD 209458 b	HD 209458	1999	This first exoplanet found to be transiting had already been discovered by the radial velocity method. This is also the first planet that has been detected through more than one method.
First planetary-mass companion directly imaged	2M1207 b	2M1207	2004/ 2005	May be a sub-brown dwarf instead of a planet, depending on formation mechanism and definitions chosen. If it is a planet, it is the first known planet around a brown dwarf.
First directly imaged extrasolar planet orbiting a star	DH Tauri b	DH Tauri	2005	Revised masses place it below the deuterium-burning limit. May be a brown dwarf companion. DH Tauri b and GQ Lupi b were confirmed as companions within about three month in 2005. Both could be brown dwarfs. If one is a planet, it is the first planet orbiting a 'normal' star, possibly the first exoplanet directly imaged.
First planet with observed secondary eclipse	HD 209458 b	HD 209458	2005	Planet was discovered in 1999. This is the first detection of light from an object with a clear planetary origin.
First directly imaged extrasolar planet orbiting a sun-like star	AB Pictoris b	AB Pictoris	2005	It has M_J. GQ Lupi b was found earlier. May, however, be a brown dwarf companion. 1RXS J160929.1−210524 b was found later. Revised mass places it at or above the deuterium-burning limit. May be a sub-brown dwarf instead of a planet, depending on formation mechanism and definitions chosen. The orbital status of the companion was confirmed in 2010.
First planet characterized by atmospheric spectroscopy	HD 209458 b	HD 209458	2007	also by HD 189733 b was characterized spectroscopically only few month later. Any of the earlier Direct imaging exoplanets, e.g. 2M1207 b, DH Tauri b or GQ Lupi b have spatially resolved spectroscopic observations, but the objects need confirmation to be of planetary origin.
First extrasolar planet detected by indirect imaging	Fomalhaut b	Fomalhaut	2008	Discovered by a light reflecting off of a dust cloud surrounding the planet. First planet orbiting an ABO star. In 2020 this object was determined to be an expanding debris cloud from a collision of asteroids rather than a planet.
First planets directly characterized through astrometric observations	Gliese 876 b and Gliese 876 c	Gliese 876	2009
First planet detected by orbital phase reflected light variations in visible light	CoRoT-1b	CoRoT-1	2009	The planet in question had already been discovered with transit method.
First planet characterized by spatially resolved atmospheric spectroscopy	HR 8799 c	HR 8799	2010	Several spectra of Direct imaging exoplanets might be earlier, but the objects need confirmation to be of planetary origin. Especially AB Pictoris b is a candidate, if its mass is confirmed to be M_J.
First planets detected through ellipsoidal light variations of the host star	HAT-P-7b	HAT-P-7	2010
First planets detected through transit timing variation method	Kepler-9b, Kepler-9c	Kepler-9	2010	Transit-timing variation was used to confirm both planets detected through transit method.
First planet detected through transit duration variation method	Kepler-16b	Kepler-16	2011	Orbital motion of the three-body system Kepler-16 causes variations of the duration of stellar eclipses and planetary transits.
First planet detected with eclipsing binary timing with well-characterized orbit	Kepler-16b	Kepler-16	2011	Kepler-16b itself was detected through transit method. There are stars with earlier detections through eclipsing binary timing. However, either those signals have matched with unstable orbits or the exact orbits are not known.
First planet detected by light variations due to relativistic beaming	TrES-2b	TrES-2A	2012
First tilted multi-planetary system discovered	Kepler-56b, c and d	Kepler-56	2013
First extrasolar planet detected through polarimetry	DH Tauri b / GSC 6214-210 b	DH Tauri / GSC 6214-210	2021	"polarization of several tenths of a percent for DH Tau B and GSC 6214-210 B in H-band"... "unlikely to be caused by interstellar dust."... "the polarization most likely originates from circumsubstellar disks." Both companions may be brown dwarfs or exoplanets. Polarized scattered light was found for HD 189733 b in 2008. It could not be confirmed and was disputed by two separate teams. Possibly a "Saharan dust event over the La Palma observatory in 2008 August". HD 189733 b was discovered in 2005.