The star system closest to our own sun hosts a planet with roughly Earth's mass and may harbor other alien worlds as well, a new study reports.
Astronomers detected the alien planet around the sunlike star Alpha Centauri B, which is part of a three-star system just 4.3 light-years away from us. The newfound world is about as massive as Earth, but it's no Earth twin; its heat-blasted surface may be covered with molten rock, researchers said.
The mere existence of the planet, known as Alpha Centauri Bb, suggests that undiscovered worlds may lurk farther away from its star — perhaps in the habitable zone, that just-right range of distances where liquid water can exist.
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I have a feeling that another Earth will be discovered soon and we may be surprised that it is in our stellar neighborhood. It may be close enough to share comets with and even some complex molecules with.