Ultra-Distant Galaxy Spied Amidst Cosmic “Dark Ages”
With the combined power of NASA’s Spitzer and Hubble Space Telescopes, as well as a cosmic magnification effect, a team of astronomers, including Carnegie’s Daniel Kelson, have spotted what could be the most distant galaxy ever seen. Light from the young galaxy captured by the orbiting observatories was emitted when our 13.7-billion-year-old universe was just 500 million years old. Their work is published September 20 by Nature.
The far-off galaxy existed within an important era when the universe just emerged from the so-called cosmic Dark Ages. During this period, the universe went from a dark, starless expanse to a recognizable cosmos full of galaxies. The discovery of the faint, small galaxy therefore opens up a window into the deepest, remotest epochs of cosmic history.
Light from the primordial galaxy traveled approximately 13.2 billion light-years before reaching NASA’s telescopes. In other words, the starlight snagged by Hubble and Spitzer left the galaxy when the universe was just 3.6 percent of its present age.