Which star is closest to Earth?

The closest star to Earth is, of course, the Sun, at about 150 million kilometres away. Beyond the Solar System, the nearest star is Proxima Centauri, a small red dwarf about 4.24 light-years away — roughly 40 trillion kilometres. It is part of the Alpha Centauri system, a group of three gravitationally bound stars. Proxima is far too faint to see with the naked eye despite its closeness, because red dwarfs are dim. Astronomers have discovered at least two planets orbiting Proxima Centauri, including Proxima b, which lies in the zone where liquid water could in principle exist.