February 18, 2009 Computational Cosmology – the use of simulations to shed light on astronomical mysteries – has provided scientists with a glimpse of what the universe may have looked like 500 million years after the Big Bang, when the first galaxies were forming in the universe’s “reionization” stage. The images, produced by scientists at Durham University, will provide researchers with key insights into dark matter, which remains frustratingly elusive, despite being first proposed in 1933 and making up an estimated 80% of the universe.
The findings chart where galaxies first appeared in the “cosmic dawn” of the universe, and how they morphed to their current status, 13 billion years later. By tracking the progress of the universe during that period, scientists can gauge the effects of dark matter, and hopefully determine some of its characteristics.
Lead author, Alvaro Orsi, a research postgraduate in Durham University’s Institute for Computational Cosmology (ICC), said: “We are effectively looking back in time and by doing so we hope to learn how galaxies like our own were made and to understand more about dark matter. The presence of dark matter is the key to building galaxies – without dark matter we wouldn’t be here today.”
Co-author Dr Carlton Baugh, a Royal Society Research Fellow, in the ICC, at Durham University, said: “Our research predicts which galaxies are growing through the formation of stars at different times in the history of the Universe and how these relate to the dark matter. We give the computer what we think is the recipe for galaxy formation and we see what is produced which is then tested against observations of real galaxies.”
The data is published in the Monthly Notices of the Royal Astronomical Society and was funded by the Science and Technology Facilities Council (STFC) and the European Commission.