Precession of the Earth's Rotation Axis

Websites on the precession of the Earth's rotation axis:

• http://csep10.phys.utk.edu/astr161/lect/time/precession.html
• http://earthobservatory.nasa.gov/IOTD/view.php?id=541
• http://hyperphysics.phy-astr.gsu.edu/hbase/solar/earthprecess.html
• http://astro.wsu.edu/worthey/astro/html/lec-precession.html
• http://www.astro.cornell.edu/academics/courses/astro201/earth_precess.htm
• http://starchild.gsfc.nasa.gov/docs/StarChild/questions/question64.html
• http://apod.nasa.gov/apod/ap150508.html
• http://www.columbia.edu/itc/ldeo/mutter/jcm/Topic2/Topic2.html