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Why Mars appears to loop the loop in the night sky

submitted by Hybrid

1 decade 4 years 7 months 3 weeks ago

Another excerpt from the BBC's Wonders of the Solar System. In this clip, Professor Brian Cox explains why when you plot the motion of Mars in the sky, it appears to loop the loop occasionally.

This was a key discovery in early astronomy in proving that the Earth was not the centre of the Solar Sytem.