Our first mystery arose in 1933, when Swiss-born astrophysicist Fritz Zwicky attempted to estimate the total mass of a cluster of galaxies. But he encountered a problem. As background, the more mass an object has, the greater it’s gravitational pull – the force that attracts other objects. The greater an object’s gravitational pull, the faster objects rotating around it will move. Zwicky noticed that galaxies at the edge of the cluster were rotating way too fast for the mass he calculated; to account for speed, the cluster had to be about 400 times more massive.
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Showing posts with label dark matter. Show all posts
Showing posts with label dark matter. Show all posts
Monday, June 20, 2011
Dark Matter and Dark Energy
Space. As far as frontiers go, it’s pretty final – and even more mysterious. In this spirit, today’s post covers two of astrophysics’ most brain-boggling theories: dark matter and dark energy.
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