00:32 - Source: CNN
NASA: Kepler planet may be habitable

Story highlights

Researchers find an Earth-sized planet that may be habitable

It "proves the existence of worlds that might be similar to our own," institute says

Scientists are looking for emissions that could suggest extraterrestrial life

Previously discovered worlds were larger than Earth

CNN —  

It’s like finding a needle in a universe-wide haystack. Researchers have located a planet roughly the size of Earth that could be habitable.

Designated Kepler-186f, the planet is 490 light-years away. But in the search for worlds similar to ours, nothing has come closer.

“This is the first definitive Earth-sized planet found in the habitable zone around another star,” said Elisa Quintana of the Search for Extraterrestrial Intelligence (SETI) Institute at NASA. “Finding such planets is a primary goal of the Kepler space telescope.”

courtesy Danielle Futselaar

“This discovery not only proves the existence of worlds that might be similar to our own but will undoubtedly shape future investigations of exoplanets that could have terrestrial surface environments,” the institute said in an announcement Thursday.

After spotting it, the institute wasted no time searching for emissions that could indicate the presence of ETs. So far, no emissions have been found.

The size – estimated to be 10% larger than Earth – and distance from its star don’t just make for interesting factoids. They give scientists hope that Kepler-186f might sustain life as we know it.

Of nearly 1,800 “confirmed exoplanets” that have been found, approximately 20 orbit their host stars within habitable zones, where it’s believed surface water would not freeze or boil. In 2011, NASA announced that Kepler had observed five planets approximately the size of Earth and in the habitable zone.

But the “previously discovered worlds are larger than Earth, and consequently their true nature – rocky or gaseous – is unknown,” the SETI Institute said in a writ