We live in interesting times as the Kepler telescope keeps us surprising. Yesterday we NASA announced that they found the most earth-like exoplanet so far.
The start of Kepler 452b is 1.5 billion years older and 10 percent greater than our Sun. The planet has a year of just 385 days and is 5 percent farther away from its start than Earth is from the Sun. And because its mas is about five times Earth’s, its surface gravity is two times ours.
Despite the many similarities it’s unlikely that there’s currently life at Kepler 452b as it’s now probably too hot. Because its star is older than our Sun, which is of the same class, it’s also much brighter and hence hotter. Our planet will suffer a similar fate in a billion years as our Sun will gradually become brighter and brighter.
However, this raises the question whether there might have been live at Kepler 452b in the past. If they have existed, they might have escaped their dying planet to live in space habitats. Of course, this is wild speculation with many ifs.
Anyway there’s no prospect of an invasion from them, if they exist, as the planet is 1,400 light-years away from us. That’s simply too far away to travel just. Even if the former habitants of Kepler 452b would have left their planetary system for good it would take them many thousands if not millions of years to come here, while they would have encountered many other stars and planets and their journey.