A newly discovered planet around a distant star may jump to the top of the list of places where scientists should go looking for alien life.
The alien world known as LHS 1140b is rocky, like Earth. It is only 40 light-years away from our solar system (essentially, down-the-street in cosmic terms), and sits in the so-called habitable zone of its parent star, which means liquid water could potentially exist on the planet’s surface. Several other planets also meet those criteria, but few of them are as prime for study as LHC 1140b according to the scientists who discovered it, because the type of star the planet orbits and the planet’s orientation to Earth make it ripe for investigations into whether it’s the kind of place where life could thrive.
“This is the most exciting exoplanet I’ve seen in the past decade,” Jason Dittmann, a postdoctoral fellow at the Harvard-Smithsonian Center for Astrophysics (CfA) and lead author on the paper describing the discovery, said in a statement from CfA. “We could hardly hope for a better target to perform one of the biggest quests in science — searching for evidence of life beyond Earth.”
Thousands of exoplanets have been discovered orbiting stars other than the sun in the last 20 years. Many of those planets meet some of the basic requirements for hosting life as we know it — they’re rocky like Earth (rather than gaseous, like Saturn or Jupiter) and they sit in the habitable zone of their parent star.
LHS 1140b meets those initial requirements. Through multiple observations, Dittmann and colleagues determined that the planet receives about 0.46 times as much light from its parent star as Earth receives from the sun. The planet is about 1.4 times the diameter of Earth and 6.6 times its mass, which makes it a so-called super-Earth and suggests it is also rocky.