Breaking News: Kepler Team Spots First Earth-Sized Exoplanets

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The video above sums up the big astro-news of the day: NASA’s Kepler mission has confirmed the existence of not one but TWO Earth-sized planets orbiting a Sun-like star 1,000 light-years away. This is a big deal!

Earlier this month the team announced the discovery of Kepler-22b, an exoplanet orbiting its star well within its habitable zone – the region where liquid water can exist without boiling off or freezing altogether.

But Kepler-22b is nearly 2 1/2 times the size of Earth and is suspected to be less dense, leading researchers to believe it may have a thick atmosphere and a surface not conducive to liquid water and/or life. (More study is still needed on that though.)

Artist's concept of Kepler-20f, a rocky planet 1.03 times the radius of Earth. Credit: NASA/Ames/JPL-Caltech

These newly-announced exoplanets, designated Kepler-20e and -20f, are much nearer to Earth size BUT orbit their star too closely to be habitable. So although they are truly Earth-sized exoplanets they can’t be called “Earthlike”, not with temperatures at or above the 1000-degree F mark.

Still, this is the first time that small rocky worlds orbiting other stars have been confirmed… it’s one more step toward that all-important discovery of a real “alien Earth”!

News like this is why when the Kepler team talks, everyone listens.

Read more about this exciting announcement in my article on National Geographic News or in Nancy Atkinson’s article on Universe Today.

How Kepler-20e and f compares to Earth and Venus. The new exoplanets are "rocky like Earth but with scorching temperatures."