Nearly 4,300 exoplanets have been discovered by astronomers, and it’s quite obvious now our galaxy is filled with them. But the point of looking for these new worlds is more than just an exercise in stamp collecting—it’s to find one that could be home to life, be it future humans who have found a way to travel those distances or extraterrestrial life that’s made a home for itself already. The best opportunity to find something like that is to find a planet that resembles Earth.
And what better way to look for Earth 2.0 than to search around stars similar to the sun? A new analysis of exoplanet data collected by NASA’s Kepler space telescope, which operated from 2009 to 2018, has come up with some new predictions for how many stars in the Milky Way galaxy that are comparable to the sun in temperature and age are likely to be orbited by a rocky, potentially habitable planet like Earth. When applied to current estimates of 4.1 billion sun-like stars in the galaxy, their model suggests there are at minimum 300 million with at least one habitable planet.
The model’s average, however, posits that one in two sun-like stars could have a habitable planet, causing that figure to swell to over 2 billion. Even less conservative predictions suggest it could be over 3.6 billion.