Although astronomers and cosmologists long believed in the existence of planets outside our solar system, such worlds remained purely theoretical until as recently as the early 1990s. Since then, the ever-quickening pace of discovery has filled the roster of possible and confirmed planetary candidates with first tens, then hundreds and now thousands of distant worlds.
In this article, I’ll take you on a tour through the history of planet hunting and into its future. Along the way, we’ll take a look at some of the most significant discoveries, including the candidates most suitable for life as we know it.