Science Alert reports:

There are many unanswered questions about our place in the Universe. Why are we here? What is the likelihood of our existence? Could there be others like us out there in the galaxy?

One of the numbers that could help us answer these questions is this: How many rocky planets like Earth are orbiting stars like the Sun at a temperate distance amenable to life as we know it? Now, we have an answer, based on data from the retired Kepler space telescope.

It’s around 300 million.

That’s not necessarily an exact number, but it does give us a rough baseline to work from as we search for potentially life-supporting worlds in our galaxy.

“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 astronomer Steve Bryson of 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.” [Continue reading…]