11-December-2007, 11:45 PM
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Vulcan Administrator
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Join Date: Oct 2001
Location: Greenbelt, MD
Posts: 26,002
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Uranus and Neptune switched places?
Solving solar system quandaries is simple: Just flip-flop the position of Uranus and Neptune
Quote:
Four billion years ago, early in the solar system’s evolution, Uranus and Neptune switched places.
This is the result of recent work by Steve Desch, assistant professor in the School of Earth and Space Exploration at Arizona State University. The work appears in this week’s Astrophysical Journal. Desch based his conclusion on his calculations of the surface density of the solar nebula. The solar nebula is the disk of gas and dust out of which all of the planets formed. The surface density – or mass per area – of the solar nebula protoplanetary disk is a fundamental quantity needed to calculate everything from how fast planets grow to the types of chemicals they are likely to contain.
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Everything I need to know I learned through Googling.
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