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Gravitational Lensing in the Galaxy Cluster Abell 2218
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NASA / A. Fruchter / STScI

Gravitational Lenses - Nature's Telescope

The possibility that light could be bent by gravity was predicted by Albert Einstein. This was seen soon after he predicted it. People normally think of glass or plastic lenses as bending light. So we call any object that bends light rays using gravity a "gravitational lens."

In the cluster Abell 2218 (pictured here), distant blue galaxies behind the large cluster of galaxies are "squished" into a circular shape around the middle of the foreground cluster. This is from gravitational lensing.

Last modified July 23, 2008 by Randy Russell.

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