What was the first exoplanet ever discovered?
The first confirmed exoplanets were PSR B1257+12 c and its siblings, announced in 1992: worlds orbiting not a sun but a pulsar, the spinning corpse of a star that had already exploded. Everything about PSR B1257+12 c →
| # | World | Discovered | Method |
|---|---|---|---|
| ★ 1 | PSR B1257+12 c | 1992 | Pulsar Timing |
| 2 | PSR B1257+12 d | 1992 | Pulsar Timing |
| 3 | PSR B1257+12 b | 1994 | Pulsar Timing |
| 4 | 51 Peg b | 1995 | Radial Velocity |
| 5 | 16 Cyg B b | 1996 | Radial Velocity |
| 6 | 47 UMa b | 1996 | Radial Velocity |
| 7 | 55 Cnc b | 1996 | Radial Velocity |
| 8 | 70 Vir b | 1996 | Radial Velocity |
| 9 | tau Boo b | 1996 | Radial Velocity |
| 10 | ups And b | 1996 | Radial Velocity |
| 11 | GJ 876 b | 1998 | Radial Velocity |
| 12 | HD 168443 b | 1998 | Radial Velocity |
| 13 | HD 187123 b | 1998 | Radial Velocity |
| 14 | HD 195019 b | 1998 | Radial Velocity |
| 15 | HD 210277 b | 1998 | Radial Velocity |
| 16 | HD 217107 b | 1998 | Radial Velocity |
| 17 | GJ 86 b | 1999 | Radial Velocity |
| 18 | HD 10697 b | 1999 | Radial Velocity |
| 19 | HD 130322 b | 1999 | Radial Velocity |
| 20 | HD 134987 b | 1999 | Radial Velocity |
| 21 | HD 177830 b | 1999 | Radial Velocity |
| 22 | HD 192263 b | 1999 | Radial Velocity |
| 23 | HD 209458 b | 1999 | Radial Velocity |
| 24 | HD 222582 b | 1999 | Radial Velocity |
| 25 | HD 75289 b | 1999 | Radial Velocity |
Showing the top 25 of 6,311 that qualify.
The first planets beyond the Sun were found in the least likely place. A pulsar sweeps a beam past Earth with the regularity of an atomic clock, and in 1992 Aleksander Wolszczan and Dale Frail showed that one pulsar's beat was arriving a few thousandths of a second early and late in a repeating pattern that only orbiting planets could explain. Those worlds are almost certainly a second generation, formed from the debris of the supernova that made the pulsar.
Three years later came the discovery most people mean by the question: 51 Pegasi b, the first planet found around an ordinary Sun-like star, detected by the wobble it induced. It won Michel Mayor and Didier Queloz a share of the 2019 Nobel Prize in Physics, and it opened the era this catalog documents. Both firsts are real; they answer slightly different questions.
What was the first exoplanet ever discovered?
The first confirmed exoplanets were PSR B1257+12 c and its siblings, announced in 1992: worlds orbiting not a sun but a pulsar, the spinning corpse of a star that had already exploded.
When was the first exoplanet discovered?
In 1992, around a pulsar. The first planet found orbiting a normal, Sun-like star came in 1995: 51 Pegasi b, a hot Jupiter completing an orbit every four days.
Why was 51 Pegasi b such a surprise?
Because nothing in the theory of the day allowed it. A Jupiter-sized planet was supposed to form far from its star, where it is cold enough for ice, yet this one was orbiting closer than Mercury. It forced a rewrite of how planetary systems form and move.
Are there earlier claims than 1992?
Several, and none of them stood up in the way these did. Candidates were announced through the twentieth century and later withdrawn or reattributed to stellar activity, which is why the confirmed record starts here.
Keep exploring: all records · planets found by pulsar timing · every year of discoveries