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Universe's first life might have been born on carbon planets

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"This work shows that even  stars  with a tiny fraction of the  carbon  in our solar system can host planets," says lead author and Harvard University graduate student Natalie Mashian. "We have good reason to believe that alien life will be carbon-based, like life on Earth, so this also bodes well for the possibility of life in the  early universe ," she adds. The primordial universe consisted mostly of hydrogen and helium, and lacked chemical elements like carbon and oxygen necessary for life as we know it. Only after the first stars exploded as supernovae and seeded the second generation did planet formation and life become possible. Mashian and her PhD thesis advisor Avi Loeb (Harvard-Smithsonian Center for Astrophysics) examined a particular class of old stars known as carbon-enhanced metal-poor stars, or CEMP stars. These anemic stars contain only one hundred-thousandth as much iron as our Sun, meaning they formed before interstellar space had been wid

How and when did the first planets form in our universe?

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While conducting a survey of metal-poor or very ancient stars, astronomers discovered one of the oldest planetary systems known so far. Astronomers hope to use this system to begin to understand how and when the first planets formed in our universe. In late March, 2012, European astronomers announced that they had discovered a planetary system around a  metal-poor  star, that is, a star containing mainly hydrogen and helium, the two ingredients thought to have been present at the Big Bang. In other words, this star and its two Jupiter-sized planets appear to be survivors from the extremely early universe. The star is HIP 11952, and it’s not the only very ancient star known to have planets. But, at an estimated age of 12.8 billion years, this exoplanet system is one of the oldest systems known so far.

Journey Through The Universe - HD Documentary

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Journey Through The Universe