Credit: NASA/JPL-Caltech/T. Pyle (SSC)

Shimmering in Infrared Light

This artist's conception shows what a dusty and bright galaxy located billions of light-years away might look like close up if viewed in infrared light. Galaxies like these are so far away and so drenched in dust, they appear invisible to optical telescopes.

NASA's Spitzer Space Telescope uncovered a hidden population of dusty galaxies like these using its heat-seeking infrared eyes. The galaxies are among the brightest in the universe and are located 11 billion light-years away back to a time when the universe was 3 billion years old. The universe is currently believed to be 13.5 billion years old.

Astronomers are not sure what is lighting up these cosmic behemoths, but they speculate that quasars -- the most luminous objects in the universe -- may be lurking inside.

The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory. This website is maintained by the Spitzer Science Center, located on the campus of the California Institute of Technology and part of NASA's Infrared Processing and Analysis Center. Privacy Policy