Liquid Acquisition: Two new scenarios ramp up debate over how Earth got its water

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Source:  Ron Cowen, Science News (subscription needed)
Excerpt: Brad Hansen of UCLA began exploring a scenario in which the inner solar system's planets coalesced from materials confined to a width of 0.7 to 1.0 times Earth's distance from the Sun, a much narrower disk than normally considered. … Alessandro Morbidelli and his collaborators ... thought Jupiter's movement could be the culprit. …after the gaseous Jupiter was fully formed, a scant few million years after the birth of the solar system … gas from the planet-forming disk spiraled into the sun, Jupiter was dragged along plowing through and emptying the asteroid belt and entering the inner solar system…. Jupiter … would have placed icy outer solar system material on elongated orbits aimed into the inner solar system … bashed into Earth, baptizing the planet with water.

 www.sciencenews.org/view/feature/id/68194/title/Liquid_Acquisition

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