Sixty Symbols

Wobbly Earth - Sixty Symbols (2011x31)

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Axial precession is the reason the Earth's axis has a long-term but quite dramatic "wobble", as explained here by Roger Bowley and Mike Merrifield. Visit our website at http://www.sixtysymbols.com/ We're on Facebook at http://www.facebook.com/sixtysymbols And Twitter at http://twitter.com/#!/periodicvideos