

Researchers using the Hubble and Spitzer telescopes have identified what they believe may be the youngest star-forming galaxy ever observed, seen just 700 million years after the birth of the universe itself.

This period in the history of the universe is thought to be a kind of cosmic "dark age," when space was suffused with clouds of cold hydrogen gas that had yet to coalesce into stars and galaxies. The galaxy observed, which astronomers think they are seeing as it was 12.8 billion years in the past, would thus have been one of the early points to light up with new-formed stars.

"This galaxy presumably is one of the many galaxies that helped end the dark

ages," said astronomer Larry Bradley of Johns Hopkins University, and leader of the study. "Astronomers are fairly certain that high-energy objects such as quasars did not provide enough energy to end the dark ages of the universe. But many young star-forming galaxies may have produced enough energy to end it."

Astronomers were able to take advantage of a natural lens in space to see so far back in time and space. A massive cluster of galaxies called

Abell 1689, about 2.2 billion light years away, exerts enough gravitational pull on the surrounding space to bend the path of light from objects behind it.

This natural "gravitational lens" effect essentially magnified the distant light by nearly 10 times, making it bright enough for Spitzer and Hubble to detect. However, it is still invisible in the ordinary light spectrum, because the expansion of the universe over time has stretched the wavelength of the light emitted by the young galaxy into the infrared spectrum.

By today's standards, it's a tiny galaxy, the mass of just a few billion stars like our Sun. But astronomers believe that was typical for early star-forming galaxies.

Astronomers Find One of the Youngest and Brightest Galaxies in the Early Universe [Hubble]

(Image: The "dark ages" galaxy, as seen by Hubble and Spitzer. The largest image shows the region of space involved, while the Hubble and

Spitzer insets show the barely visible image as seen in infrared light.

Credit: NASA; ESA; L. Bradley (Johns Hopkins University); R. Bouwens

(University of California, Santa Cruz); H. Ford (Johns Hopkins

University); and G. Illingworth (University of California, Santa Cruz))