On Thu, 23 Sep 1999 you wrote:

> What direction does the moon move in the sky, in relation to the northern
> hemisphere? (east or west)

Hello,

The answer here depends on what you mean exactly by how the moon moves in
the sky. If you are talking about how the moon appears to move as seen by
somebody watching from the Earth and comparing the moon's position to
their horizon (i.e. the ground, or trees, or houses, etc.), then the moon
moves from East to West, just like the sun, stars, and planets all do.
This movement is caused by the Earth's rotation. If, however, you are
comparing the moon's position to the background stars, then the moon moves
from west to east, due to its orbital motion. This effect is easily seen
by going out at the same time of night for two (or more) nights in a row
and comparing the moon's position with nearby bright stars.

Thanks for writing!
Sincerely,
Kurtis Williams

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