The discovery of 51 Pegasi b marked a turning point in the field of astronomy and exoplanet research. It was located in the Pegasus constellation, roughly 50 light-years from Earth, by Swiss astronomers Michel Mayor and Didier Queloz. Using the radial velocity method, they detected the subtle wobble in the motion of the star 51 Pegasi, caused by the gravitational pull of an orbiting planet. This method allowed them to infer the planet's existence and its mass, leading to the confirmation of 51 Pegasi b as the first exoplanet around a sun-like star. The planet itself is classified as a hot Jupiter due to its large size and close proximity to its star, with a year lasting just 4.2 Earth days.

The detection of 51 Pegasi b opened up an entirely new chapter in astronomy. Prior to this discovery, the existence of other planetary systems was a subject of speculation. Mayor and Queloz's work not only proved that such systems exist but also ignited interest in the search for other potentially habitable planets outside our solar system. Their findings catalyzed numerous follow-up studies and missions aimed at discovering more exoplanets, significantly expanding the field of astrobiology and our understanding of the conditions necessary for life.

The implications of finding exoplanets are profound, as it encourages questions about the potential for life beyond Earth. This discovery has paved the way for advanced space telescopes and missions designed to explore the atmospheres of distant worlds. The subsequent advancements in technology and methodology have enhanced the capability of astronomers to identify planets even smaller or farther away than 51 Pegasi b, revealing a rich diversity of planetary environments. As exoplanet research evolves, the possibilities of discovering new life forms and understanding the cosmos grow ever more tantalizing.