When Galaxies Collide

29 October 2012 - Come to tonight's Sydney Ideas lecture to hear what happens when galaxies crash into each other, and how astrophysicists go about the work of reconstructing past collisions. "Studying galactic interactions is like sifting through the forensic evidence at a crime scene," says Richard de Grijs from the Kavli Institute for Astronomy & Astrophysics, Peking University. "Astronomers wade through the debris of a violent encounter, collecting clues so that they can reconstruct the celestial crime to determine when it happened." Professor de Grijs will look at the case of Messier 82, a small, nearby galaxy that long ago bumped into its larger neighbour, Messier 81. He will present new infrared and visible-light pictures from the Hubble Space Telescope which reveal for the first time important details of large clusters of stars which arose from the interaction. Professor de Grijs is the 2013 Selby Fellow of the Australian Academy of Science. The fellowships are aimed at increasing public awareness of science by bringing distinguished overseas scientists to Australia for a lecture tour. Professor de Grijs will be visiting the ARC Centre of Excellence for All-sky Astrophysics (CAASTRO) on campus this week.