Strange ‘Lava World’ Is Most Earthlike Alien Planet Yet

space.com

A puzzling alien planet is the closest thing to an Earth twin in size and composition known beyond our solar system, though it’s far too hot to support life, scientists say.
The exoplanet Kepler-78b, whose supertight orbit baffles astronomers, is just 20 percent wider and about 80 percent more massive than Earth, with a density nearly identical to that of our planet, two research teams report in separate papers published online today (Oct. 30) in the journal Nature.
“This is the planet that, in many respects, is the most like Earth that’s been discovered outside our solar system,” said Andrew Howard, of the University of Hawaii at Manoa’s Institute for Astronomy and lead author of one of the studies. “It has approximately the same size. It has the same density, which means it’s made out of the same stuff as Earth, in all likelihood.”