20 years ago, astronomers discovered the first planet orbiting a sun-like star outside the solar system.
The groundbreaking discovery of the first planet to be found orbiting a star similar to the sun occurred 20 years ago with the discovery of 51 Pegasi b on Oct. 6, 1995. The discovery led to an entirely new field of study and started the search for planets similar to our own beyond the solar system.
51 Pegasi b resides approximately 50 light-years away in the constellation Pegasus. It is approximately half the size of Jupiter and orbits its host star once about every 4 days. It belongs to a category of planets known today as exoplanets. Exoplanets are a classification for planets that exist beyond the solar system which orbit stars, stellar remnants, or brown dwarfs.
The discovery of 51 Pegasi b proved that planets outside the solar system orbit sun-like stars. For centuries it has been suggested that planets may exist beyond our solar system, however, it wasn’t until recently that it became possible to detect them. 51 Pegasi b also altered theories on planet formation. It was previously thought that planets of its size could not orbit so close to their ...