Astronomers Find “Mega-Earth”

Via the Washington Post:

Astronomers have discovered a surprising planet, a rocky world with 17 times the mass of Earth. There have been “Super-Earths” discovered before, but this one is in a league of its own. The scientists call it a “Mega-Earth.” Discovered by NASA’s Kepler space telescope and announced Monday at an astronomy meeting in Boston, this planet, officially named Kepler-10c, scrambles the equations that dictate how massive a rocky planet can be without ballooning into a Jupiter-like gas giant. The theorists didn’t see this coming. The orthodoxy was that, beyond about 10 Earth masses, a planet would hold on to so much hydrogen gas that it would become like Jupiter or Saturn. Kepler-10c suggests that plus-size planets can stay rocky, with clearly defined surfaces, rather than becoming gaseous and bloated. That means there’s more real estate out there for life as we know it on Earth.

Mega-Earth is too close to its sun to be habitable and only has a 45-day year.