View Single Post
  #13  
Old December 20th, 2007, 08:55 PM
Spoo's Avatar

Spoo Spoo is offline
First Lieutenant
 
Join Date: Jan 2001
Location: Toledo, OH
Posts: 641
Thanks: 0
Thanked 0 Times in 0 Posts
Spoo is on a distinguished road
Default Re: Planet Rotation Speeds

Quote:
MasterChiToes said:
The Terrestrial planets can be expected to turn slower due to 'tidal forces' dissipating their rotational angular momentum. If you check out the length of a day on ancient earth, it was much shorter than the Jovian planets.

In general, for a stable climate, I would agree that smaller planets better turn slower.
I think you would have to make a number of assumptions about the event that formed the Moon to know what Earth's original rotation rate was. Although, I agree that it must have slowed since then.

Also, tidal forces would have little effect on Mars (two very small moons), and none on Venus (no moons) - although something must have happened to Venus to make it rotate "backwards". It's generally thought that terrestrial planets with a satellite as large as the Moon are very rare. However, Mercury's rotation is very strongly determined by tidal forces from the Sun.
__________________
Assume you have a 1kg squirrel
E=mc^2
E=1kg(3x10^8m/s)^2=9x10^16J
which, if I'm not mistaken, is equivilent to roughly a 50 megaton nuclear bomb.
Fear the squirrel.
Reply With Quote