Astronomers have found the first evidence of a collision between exoplanets. Though 2 planets around the star Kepler-107 are both the same size and orbit at about the same distance, one is twice as dense as the other, suggesting its outer layers were stripped off when it got smacked by another world

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Astronomers have found the first evidence of a collision between exoplanets. Though 2 planets around the star Kepler-107 are both the same size and orbit at about the same distance, one is twice as dense as the other, suggesting its outer layers were stripped off when it got smacked by another world