All these worlds are not yours

With the U.S. election hogging our collective attention for weeks, you might have missed the big announcement that came out of the world of astronomy recently: There are at least 300 million “potentially habitable” planets in our galaxy, rocky worlds that orbit stars like our Sun that might have liquid water on their surfaces.

This mind boggling galactic real estate estimate is the culmination of years of hard work by scientists who study extrasolar planets, or exoplanets. Dozens of these researchers spent two years crunching the data collected by NASA’s Kepler space telescope, which scanned more than half a million stars for planetary signals between 2009 and 2018 and confirmed nearly 3,000 exoplanets. Focusing on planets similar in size to Earth that orbit stars similar in age and temperature to our Sun, the scientists made a galactic extrapolation. The results, which will be published in an upcoming edition of The Astronomical Journal, suggest there are hundreds of millions of potential Earth lookalikes even under the most conservative assumptions. While we do not yet know if any these worlds are actually habitable, this points to a lot of chances for habitable conditions, and life, to exist elsewhere.

It does not, however, suggest that we humans are going to be planting terrestrial flags across the galaxy anytime soon.

Despite what so much science fiction, and some very solid space tourism propaganda from NASA, would have us believe, our descendants are unlikely to visit many (or any) of these cosmic cousins for a simple reason: Space is really, really big. And in a universe bound by the laws of physics—meaning no faster-than-light travel—we simply can’t get around it very fast.