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Yes indeedy! The Earth's axis is all over the place. This isn't unexpected, of course, since scientists have been on top of the gyrations of the planet for several thousand years. The key thing to remember is that "change" is all relative. On a yearly basis, the 23-degree tilt of the Earth's axis moves around the sun so that the Northern Hemisphere points away from the sun part of the year and points toward the sun for part of the year. For a good illustration of what we mean, check out the explanation at Time, Sun and the Stars. There you'll also find information on the more long-term shift known as "the precession of the equinoxes." This change isn't measured in relation to the sun, but rather to the other
stars in the sky. Every 26,000 years the Earth's axis goes through a cycle of pointing to different parts of the sky. If you can imagine the conical pattern of a spinning top, then you've got a good idea of what the precession looks like. Check out this University of Tennessee Astronomy Syllabus for more on the phenomenon. Finally, for answers about all things rotational, simply visit our sister (or brother) columnist at Ask a Space Scientist. This NASA site covers everything you could possibly want to know about our little spinning globe.
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