As things stand, the Earth is the only known example of a habitable world in the entire universe – even the other planets in our solar system, as far as we know, do not (or no longer) harbor life.
On a galactic scale however, worlds capable of supporting life may be literally everywhere.
According to new NASA research based on data from the now-defunct Kepler space telescope, roughly half of all stars with a similar temperature to our own are likely to host a terrestrial planet capable of supporting liquid water on its surface.
This equates to around 300 million potentially habitable worlds across the Milky Way.
Some of these could also be relatively close – as little as 20 light years away.
“Kepler already told us there were billions of planets, but now we know a good chunk of those planets might be rocky and habitable,” said study author Steve Bryson from NASA’s Ames Research Center.
“Though this result is far from a final value, and water on a planet’s surface is only one of many factors to support life, it’s extremely exciting that we calculated these worlds are this common with such high confidence and precision.”
Just how many of these planets do support life however remains a mystery – but if even one of them does, the question of whether we are alone in the universe will have already been answered.
