On Sun, 11 Dec 2005 10:12:55 -0500, "John Zinni"
wrote:

"Ryan Evans" wrote in message
...
Do we always see the same side of the moon, or does it slowly rotate
in relation to our view?

To me, it seems quite a cooincidence that the moon rotates perfectly
such that we see the same side constantly.

RE

No coincidence. In fact it's quite common.

It's called 1-to-1 spin-orbit resonance.


"Most of the moons in the solar system are similarly locked by the tidal
fields of their parent planets."
http://physics.fortlewis.edu/Astrono...ML/AT30803.HTM

"All the large moons in our Solar System are in 1:1 spin-orbit resonances:
Those moons always show the same side to the planet, just like our Moon does
relative to the Earth."
http://www.astro.uu.nl/~strous/AA/en...rtekracht.html


Question: What major solar system object is locked into a spin-orbit
resonance with its primary that is other than 1-to-1?


answer neptune and pluto?

actually, you could include any asteroid or KBO at the respective
Langrange regions away from any planet, especially the ones at 2:3 and
2:5 resonances...

me? i've personally revoked pluto's license to be a planet...