Astronomers See Faintest, Furthest Galaxy

Farthest galaxy

The image of this faint, distant galaxy was split into three by a gravitational lens. By comparing the spectra of three images (white boxes), astronomers could show they were all the same object 13 billion light years away. Credit: Marusa Bradac/Hubble Space Telescope/W. M. Keck Observatory

May 19, 2016 — A team of scientists led by two UC Davis physicists has detected and confirmed the faintest early-universe galaxy yet. This new object, seen as it was about 13 billion years ago, could help astronomers understand the “reionization epoch” when the first stars became visible.

Gravitational lensing and a special instrument on the 10-meter telescope at the W.M. Keck Observatory on the summit of Mauna Kea, Hawaii, enabled the team to see the incredibly faint object. The findings are published in Astrophysical Journal Letters today, May 19.

“Keck Observatory’s telescopes are simply the best in the world for this work,” said UC Davis physics professor and co-team leader Marusa Bradac. “Their power, paired with the gravitational force of a massive cluster of galaxies, allows us to truly see where no human has seen before.”

Read more at UC Davis News

By Andy Fell, UC Davis News and Media Relations