This artist's impression shows the planet Proxima b orbiting the red dwarf star Proxima Centauri, the closest star to our solar system -- "only" 4.25 light-years away. Included in view is the more distant Alpha Centauri AB binary star system that Proxima orbits from afar. Now that an alien world has been confirmed to be orbiting within Proxima Centauri's "habitable zone" and is most likely a small, rocky world slightly larger than Earth, speculation rumbles as to its "Earth-like" potential. However, we currently have no idea whether Proxima b has an atmosphere and, though liquid water could exist on its surface, we have no idea if water is even there. But it's a start.
Credit: ESO/M. Kornmesser