Damsel took this image of one of our cholla with the beautiful Arizona blue sky and the waxing gibbous moon today. Invisible in this image is the fact that planet Jupiter is within a fraction of a degree of the moon today. We went out after dark and saw it this evening. Beautiful! Click on the image to enlarge.
When I looked at Jupiter and the Moon yesterday, the Moon was well to the west of Jupiter, and slightly above it, per the shadow dictated by the phase of the Moon. By that, I interpreted that the Moon was above Jupiter. Tonight, 1/21/13, the Moon is just below Jupiter, and parallel with it. That tells me something about how out of parallel the orbit of the Moon is with the Sun. Most interesting!
There is a very thorough description of the orbit of the moon around the Earth in Wikipedia:
http://en.wikipedia.org/wiki/Orbit_of_the_Moon
The moon’s orbit is at an angle of about 5 degrees from the equatorial plane of the Earth. It’s motion relative to the stars (and Jupiter on a given night) is about one lunar diameter per hour. Lunar orbital velocity is about 1km/sec.
Yes – it is very interesting.