- #1
GTrax
- 156
- 10
The moon rotates on its own axis with such exquisite precision that it turns exactly once in a time exactly equal to the time to complete its orbit around Earth. How did it get that way?
More - if there are plausible or proven explanations, then will the Earth day sometime end up equal to the Earth year? Are there other moons in the solar system that have this relationship with the planets they orbit?
I can accept if the Earth and Moon are seen as a double-planet system that had started out as a single lump that got split apart at some point and then settled together as they are now, then the rotational momentum of the pair orbiting each other might be much the same as the original, but I do not understand how this would make the synchrony inevitable, nor why it should apply only to Earth-Moon motion.
PS: This started out in fun playing Pink Floyd's "Dark Side of the Moon", and ended up with "Why don't we get to see the dark side Daddy"? Umm... err gulp :|
More - if there are plausible or proven explanations, then will the Earth day sometime end up equal to the Earth year? Are there other moons in the solar system that have this relationship with the planets they orbit?
I can accept if the Earth and Moon are seen as a double-planet system that had started out as a single lump that got split apart at some point and then settled together as they are now, then the rotational momentum of the pair orbiting each other might be much the same as the original, but I do not understand how this would make the synchrony inevitable, nor why it should apply only to Earth-Moon motion.
PS: This started out in fun playing Pink Floyd's "Dark Side of the Moon", and ended up with "Why don't we get to see the dark side Daddy"? Umm... err gulp :|