SAN ANTONIO — The discovery of Earth's galactic relative is simply out of this solar system.

Sorry, we couldn't resist. But it's true! Kepler-186f is 500 light-years away, and just might be Earth's long-lost cousin.

Sure, scientists believe there are billions of Earth-like planets in the galaxy, but this is the first time we've discovered an Earth-size planet outside our solar system right smack in the “Goldilocks zone.” A place neither too hot, nor too cold. You know, just right. Like Earth.

Unfortunately, we don't know much else. Kepler-186f is colder than Earth, scientists say, because it orbits a red dwarf star about half the size of the sun.

It is likely a rocky terrain with a similar surface gravity, meaning there may be water. But it may be a planet like Venus with a poisonous atmosphere that makes it the hottest planet in the solar system. Or it could be a planet more like Mars with a thin atmosphere, or any number of other scenarios.

The fact that this planetary cousin is more than 500 light-years away should make us appreciate the wonder in the natural environment that we all take for granted.