Balloon Analogy in Cosmology Feature Summary

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Balloon Analogy in Cosmology
Quasars are the most distant objects we can see from Earth. Their light reaches us from billions of years in the past. Astronomers know how far they really are from us because the light we see is dramatically redshifted, meaning they are moving away from us astonishingly fast. See the Balloon Analogy in Cosmology to learn more about the expansion of the universe and how astronomers use redshift to measure distances in space. Find out how you can paste galaxies on a balloon and make a model of how the universe expands.
February 1, 2011 - March 12, 2011