The Hubble Space Telescope has captured the farthest-ever view into the universe, a photo that reveals thousands of galaxies billions of light-years away.
The picture, called eXtreme Deep Field, or XDF, combines 10 years of Hubble telescope views of one patch of sky. Only the accumulated light gathered over so many observation sessions can reveal such distant objects, some of which are one ten-billionth the brightness that the human eye can see.

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