In a first of its kind, researchers have obtained the deepest ever view of the universe where over 250,000 galaxies have been detected in an area four times the size of full moon.
Astronomers at the University of Nottingham, led by Omar Almaini, Professor of Astrophysics in the School of Physics and Astronomy, presented their results at the National Astronomy Meeting based on final data from the Ultra-Deep Survey(UDS).
Several hundreds of them have been observed within the first billion years after the Big Bang and astronomers around the world can use the new images to study the early stages of galaxy formation and evolution, said the release.
The project since 2005 began taking data using the United Kingdom Infrared Telescope (UKIRT) in Hawaii to observe the same patch of sky repeatedly, building up more than 1000 hours of exposure time. Infrared makes it easier to study the distant Universe as ordinary starlight is “redshifted” to longer wavelengths due to the cosmological expansion of the Universe.
Because of the finite speed of light, the most distant galaxies are also observed very far back in time.
“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,” said Professor Almaini.
The UDS, one of the 5 projects of the UKIRT Infrared Deep Sky Survey (UKIDSS), has produced a wide range of scientific advances of the large-scale distribution of galaxies to weigh the mysterious ‘dark matter’ that pervades the cosmos.
Dr David Maltby, a postdoctoral research fellow at the University of Nottingham whose research focusses on morphological evolution of galaxies, said: “We still don’t understand why the most massive galaxies are usually elliptical in shape, while less massive galaxies tend to be disk-shaped with spiral arms. 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.”