Earliest Known Galaxies Spied in Deep Hubble Picture

Compact, ultra-blue galaxies spied for the first time in the deep universe are the most distant—and therefore the earliest—galaxies anyone has ever seen, astronomers announced today.

These galaxies started forming just 500 million years after the big bang, which is thought to have occurred around 13.7 billion years ago. That pushes back the known start of galaxy formation by about 1.5 billion years.

The objects were spotted in pictures taken by the Hubble Space Telescope's Wide Field Camera 3, a new camera installed in 2009. (See some of the first pictures taken by the upgraded Hubble.)

The Hubble images, combined with data from the Spitzer Space Telescope, show that the newfound galaxies are relatively small, and they appear very blue, a color linked to lighter elements such as hydrogen and helium.