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curiousuburb
Antimatter Man
 
Join Date: May 2004
Location: that interweb thing
 
2006-01-12, 07:18

More Mercury news this week... the current issue of Nature discusses a theory that, just like Earth's Moon and Pluto's Charon, Mercury may have had a monster impact event as part of its formation which stripped off the planet's outer layer

Quote:
New computer modeling shows that the planet Mercury might have formed in a hit-and-run collision that stripped off its outer layers.

Astronomers have long assumed that collisions played a huge role in planet formation. The early solar system would have been loaded with dust that became rock that became planets, the thinking goes. Computer models generally have objects sticking together to make ever-larger objects or, in large crashes, two objects might become gravitationally bound.

In the new scenario, a glancing blow would dramatically alter the smaller object, even disintegrating it into pieces that could be some of the space rocks that land on Earth to this day.

"You end up with planets that leave the scene of the crime looking very different from when they came in—they can lose their atmosphere, crust, even the mantle, or they can be ripped apart into a family of smaller objects,” said Erik Asphaug, a researcher at the University of California at Santa Cruz who led the work.

The idea is detailed in the Jan. 12 issue of the journal Nature.

Other scientists have modeled collision scenarios in which the remains form two objects that end orbitally bound. Earth’s Moon, for example, is thought to have been formed when a Mars-sized object slammed into our fledgling planet. Pluto’s largest satellite, Charon, may have formed in a similar impact.


... story continues...
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