NASA discovery of planet remarkably like ours gives hope for 'second Earth' - CNET

This NASA illustration imagines what the surface of Kepler-1649c might look like.

NASA/Ames Research Center/Daniel Rutter

NASA's now retired Kepler Space Telescope is the mission that keeps on giving. On Wednesday, NASA announced the discovery of what might be a very Earth-like exoplanet found lurking in old Kepler data.

Kepler ran out of fuel and went to sleep in 2018, but scientists are still combing through the observations it made during its epic hunt for planets beyond our own solar system.

Kepler-1649c is located 300 light-years from Earth. NASA described it as the "most similar to Earth in size and estimated temperature" out of the thousands of exoplanets discovered by Kepler. The planet is located in its star's habitable zone, a region where it's possible for liquid water to exist.

The fascinating exoplanet is slightly larger than Earth. It receives 75% of the amount of light we get from our own sun, which could put it in line with Earth temperatures as well. The planet was originally misidentified by a computer algorithm, but a team of scientists found it during a review of Kepler data.

This NASA graphic shows Earth in comparison to exoplanet Kepler-1649c.

NASA/Ames Research Center/Daniel Rutter

"This intriguing, distant world gives us even greater hope that a second Earth lies among the stars, waiting to be found," said NASA's Thomas Zurbuchen.

Don't pack your bags just yet. The exoplanet may look promising, but it's not necessarily going to be Earth 2.0.

Kepler-1649c is in orbit around a red dwarf, a type of star that NASA said "is known for stellar flare-ups that may make a planet's environment challenging for any potential life." The space agency also cautioned that Kepler-1649c's atmosphere is still a mystery and that the size calculations may be off.

The international research team that discovered the exoplanet published a paper on it in April in the Astrophysical Journal Letters.

"With red dwarfs almost everywhere around our galaxy, and these small, potentially habitable and rocky planets around them, the chance one of them isn't too different than our Earth looks a bit brighter," said lead author Andrew Vanderburg from the University of Texas at Austin.

We don't know if there's another Earth among Kepler's many exoplanets, but this latest discovery is fuel for the dream of one day finding life beyond our solar system.