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Why Mars appears to loop the loop in the night sky

submitted by Hybrid

1 decade 4 years 7 months 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.

3 Comments

doogle

says...

That guy's been sitting too close to the fumes. That eerie smile is just plain weird.

deathcow

says...

cool dude with a dream job

siftbot

says...

Tags for this video have been changed from 'brian cox, wonders of the solar system, line of sight, orbit, overtaking, bbc' to 'brian cox, retrograde motion, wonders of the solar system, line of sight, orbit, bbc' - edited by schmawy