User: Can you tell me about the discovery of the first exoplanet?
ChatGPT: Sure, the first exoplanet was discovered in 1995 by astronomers Michel Mayor and Didier Queloz. They used the radial velocity method to detect a planet orbiting the star 51 Pegasi, which is located about 50 light-years from Earth. This discovery was a major breakthrough in the field of astronomy, as it provided the first direct evidence that planets exist outside of our solar system.
User: That's really interesting. Can you tell me more about the radial velocity method?
ChatGPT: The radial velocity method involves measuring changes in the Doppler shift of a star's spectral lines as it is pulled back and forth by the gravitational influence of an orbiting planet. This technique has proven to be highly effective at detecting exoplanets, and has been used to discover thousands of planets to date.
