December 11, 2011
Asteroid Crash May Explain Mercury's Strange Spin
In the article I read based on a new study, "A collision with an asteroid might have set the planet Mercury whirling oddly in its orbit" (space.com).
For a long time scientists have assumed that the Sun and Mercury were tidally locked, just like our Moon is with Earth. Recently, however, scientists have observed Mercury using radar and found that the planet is rotating 3 times for every 2 orbits around the sun. "Now, researchers suggest that Mercury was once tidally locked, initially spinning in the opposite direction to its orbit" (space.com).
Mercury's largest impact crater, Caloris Basin, is the main focus for this idea due to the fact that it matches the impact predictions in size, age and location.
The full article is really interesting, I suggest you check it out!
Posted by fadmonic at December 11, 2011 02:48 PM
I thought it was interesting that the article says if tidal locking happened with the Earth and the sun, an earth day would be the same length as an earth year.
Posted by: mrkapila at December 12, 2011 08:32 PMLogin to leave a comment. Create a new account.