A new report puts the number of Earth-sized planets in our galaxy at 8.8 billion. Using data from NASA, scientists calculate there are that many stars in the Milky Way that are similar to the sun.

Each of these suns hosts at least one planet similar to Earth in size. Although these planets revolve in the not-too-hot, not-too-cold “Goldilocks zone,” they aren’t necessarily places where Earthlings would want to spend much time.

Conditions likely range from too hot to unendurable, because of poisonous atmospheres or rocky, waterless terrain. A small percentage of the planets could harbor intelligent life, although that discovery appears to be a long way off.

There will be no way of knowing whether life exists anywhere but here until humans achieve deep space travel, detect signals from an alien civilization, or observe distant worlds through super-powerful telescopes. The nearest planet that fits some criteria for being Earth-like is 70 trillion miles away. That’s a long way to go just to find out nobody’s home.

First Published November 8, 2013, 5:00 a.m.