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The moon is on the nodes when it's plane and the plane of the Earth intersect. This occurs every 18.6 years. Besides the rest of the planets on their orbital plane, the Milky Way too, has a plane. It is on a galactic scale. The Milky Way, an ellipsoid, is a squashed sphere rather than a rugby ball (5 to 1 ratio). It is 16 kiloparsecs in diameter. It is slightly reminiscent of the Andromeda Galaxy save it is irregular and of uneven density.
http://www.rc-astro.com/photo/id1034.html
On the second most outer spiral arm of the Milky Way, or, where our solar system lies, it is less dense than towards the center. Still, though the galactic case of Newton's laws is more highly complex than the solar, so apparently our Sun, on one of the spiral arms, is heading with determination towards a dark void in space between the constellations of Hercules and Lyra.
http://www.rc-astro.com/photo/id1166.html
http://www.flickr.com/photos/hshdude/2199082052/
The constellation Sagittarius is roughly the nucleus of the Milky Way. Our solar system revolves around it in it's movement through the Milky Way.
http://www.allthesky.com/constellations/sagittarius/
Our nearest neighbor is the triple binary, Alpha, Beta, and Proxima Centauri, which is also located in the Milky Way. Alpha and Beta are binary stars revolving around each other, while Proxima revolves around the pair.
http://www.allthesky.com/various/by32abcen300.html
In order to help give these facts some perspective in both speed and distance (taking into account the galactic case of Newton's laws), Earth spins at 1000 MPH (approx.) at the equator. It orbits the Sun at 66,000 MPH (approx.). Our solar system meanwhile, dashes through the Milky Way at 481,000 MPH (approx.).
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