A quartet of Earth-like worlds, each about 20% to 30% the size of our planet, circle one of our closest stellar neighbors, a new study reveals. The rocky alien worlds are close enough that future generations of humans may be able to visit them with futuristic rocket propulsion technology. However, it is unlikely that we will find any life there.
Astronomers have long suspected that there was at least one exoplanet orbiting Barnard's Star — a red dwarf with a mass around one-sixth that of the sun. At 5.97 light-years from Earth, it is the fourth-closest star to our solar system, after the three interconnected stars of the Alpha Centauri system. (Five potential planets have also been detected around the stars of Alpha Centauri, though not all of them have been confirmed yet.)
