Ultra Deep Survey Captures Over 250,000 Galaxies of the Distant Universe
University of Nottingham researchers just recently released the final data of the Ultra Deep Survey (UDS) that mapped a total area four times the size of full moon and detected over 250,000 galaxies, including several hundred observed within the first billion year after Big Bang.
"With the UDS we can study distant galaxies in large numbers, and observe how they evolved at different stages in the history of the Universe. We see most of the galaxies in our image as they were billions of years before the Earth was formed," commented Omar Almaini, Professor of Astrophysics in the School of Physics and Astronomy and leader of the study, in a statement.
In order to procure the final UDS image, Almaini and his team began taking data using the United Kingdom Infrared Telescope (UKIRT) on Hawaii in 2005. The researchers observe the same patch of sky repeatedly, obtaining more than 1,000 hours of exposure time. They utilize the power of infrared to provide the deepest view ever obtained over a large area in the sky. The researchers chose to use infrared to study the distant universe because ordinary starlight is "redshifted" to longer wavelengths due to the cosmological expansion of the Universe.
Also, due to the finite speed of light, the most distant galaxies detected by the UDS were also observed very far back in time, about a billion year after the Big Bang. This gives the researchers the chance to study the earliest galaxies after the Big Bang.
"Here in Nottingham we are aiming to understand how galaxies evolved to produce the rich diversity we see today," said Dr David Maltby, a postdoctoral research fellow at The University of Nottingham, in a press release. "By looking back in time to the early Universe we can catch these galaxies in their infancy, and observe them as they change and evolve over many billions of years."
Additionally the new deep space images can provide the researchers the measurements of the build-up of galaxies through cosmic time and new ideas regarding the large-scale distribution of galaxies to weigh the mysterious 'dark matter' that pervades the cosmos.