Scientists have found a planet way out in the cosmos that’s close in size and content to Earth — an astronomical first. But hold off on the travel plans. This rocky world is so close to its sun that it’s at least 2,000 degrees hotter than here, almost certainly too hot for life.
Astrophysicists report in the journal Nature that the exoplanet Kepler-78b appears to be made of rock and iron just like Earth. They measured the planet’s mass to determine its density and content. It’s actually a little bigger than Earth and nearly double its mass, or weight.
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