Sean Raymond

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    Where Earth Got Its Water

    A new theory shows Earth’s water was more locally sourced than ever thought before.

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    The Dwarf Planet on Our Doorstep

    The series of fortunate astrophysical events that gave us Ceres.

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    A Step-by-Step Guide to Our Solar System’s Demise

    First the oceans boil off. Then things really get serious.

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    Were It Not for Cosmic Good Fortune, We Wouldn’t Be Here

    Why Earth wasn’t swept into the dustbin of space.

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    We Were Here

    How advanced civilizations could leave us a message of their presence.

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    The Moon Is Underrated

    New research hints at what makes Earth’s moon special.

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    Comets Are More Dangerous Than We Thought

    Could a comet, not an asteroid, have killed the dinosaurs?

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    We’re the Cosmic 1 Percent But Our Solar System Isn’t a Complete Weirdo

    About half of all stars seem to have “super-Earth” planets on orbits closer to their stars than Mercury is to the Sun, but we don’t.Illustration by Vadim Sadovski / Shutterstock Is Earth unique? Once a grand philosophical question, it has, over the past two decades, become, with the discovery of thousands of planets around other […]

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    How ‘Oumuamua Got Shredded

    ‘Oumuamua may be a piece of a torn-apart comet, gravitationally launched into interstellar space, that roamed the galaxy before dropping on our doorstep.ESO / M. Kornmesser / Wikicommons Our solar system’s first houseguest—at least, the first one we have seen in our midst—is a strange one. Scientists have taken to calling it ‘Oumuamua (pronounced “Oh-MOO-ah-MOO-ah”), […]

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    I Built a Stable Planetary System with 416 Planets in the Habitable Zone

    This system is completely stable—I double-checked with computer simulations. But nature would have a tough time forming this system. If it exists, it could only have been built by a super-advanced civilization.Image by Sean Raymond / planetplanet.net When Frank Drake was a boy, growing up in 1930s Chicago, his parents, observant Baptists, enrolled him in […]