In October 2012, astronomers announced the discovery of a planet in the Alpha Centauri star system. This system contains the stars closest to the Sun—about 4.4 light-years away—and this newly discovered planet, called Alpha Centauri Bb, appears to have an orbital period of just over three days. If these measurements are correct, then the planet’s surface temperature probably exceeds 2,000 degrees Fahrenheit—as hot as a blast furnace, and far too hot to support life as we know it.