Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: North Pole




Is it also the case that the orbital axis precesses?

Not that I know of, that is, I am unaware of having seen anything
about this in any astronomy source I have read or consulted. It
could be that it does, but with a period too long for us to
notice, or an amount too small for us to notice.

I think that this answer is actually correct, but I think that there is some
evidence for it. Since the Earth's orbit lies in the ecliptic along with
other planets one might reasonably conclude that this situation has
persisted for a long time. The forces producing precession would probably
come from the other planets that also lie in the ecliptic, so there is no
torque to produce precession. The effect of the distant stars is very
small, because if it were large then all of the planets orbits would precess
to other angles and would not be lined up in the ecliptic. I think that one
may conclude that any effect is probably too small to be easily measured.

John M. Clement
Houston, TX

This posting is the position of the writer, not that of SUNY-BSC, NAU or the AAPT.