Supercomputers bring theory to life

A DEPICTION OF THE DISTRIBUTION OF MATTER IN AN OBJECT NEARLY TEN MILLION LIGHT YEARS ACROSS AND A THOUSAND TIMES THE MASS OF THE MILKY WAY. THOUSANDS OF THESE EXIST IN THE OBSERVABLE UNIVERSE. CREDIT: GREG POOLE, SWINBURNE UNIVERSITY OF TECHNOLOGY.
A DEPICTION OF THE DISTRIBUTION OF MATTER IN AN OBJECT NEARLY TEN MILLION LIGHT YEARS ACROSS AND A THOUSAND TIMES THE MASS OF THE MILKY WAY. THOUSANDS OF THESE EXIST IN THE OBSERVABLE UNIVERSE. CREDIT: GREG POOLE, SWINBURNE UNIVERSITY OF TECHNOLOGY.

Over aeons of time cosmic gas comes together, stars begin to form, supernovae explode, galaxies collide. And computational astronomers can watch it all unfold inside a supercomputer. That’s the kind of work post-doctoral fellows Rob Crain and Greg Poole are doing at the Swinburne Centre for Astrophysics and Supercomputing.

In late 2010, one of Crain’s simulations of galaxy formation appeared on the cover of the prestigious weekly British science journal, Nature. And Poole’s simulations of the evolution of the structure of the Universe have earned him a place in an international research team undertaking the largest project in the history of the Hubble Space Telescope—the CANDELS survey to investigate galaxy evolution across 12 billion years of cosmic time.

“The supercomputer is the astronomer’s laboratory,” says Darren Croton, also from Swinburne and chair of the Australian National Institute for Theoretical Astrophysics. “We use them to apply our knowledge of the Universe and build models of how we think the details work. Then we can test our models with observations.

“Supercomputing technology has really marched forward recently. And that means that theoretical astrophysics has taken off. Simulations can be used to predict where to point our billion-dollar telescopes for maximum scientific return, so we don’t waste observing time. Theorists have become valuable members of large observing teams, and help guide them and interpret their results.”

Australia’s forté in the field, says Croton, is tracking cosmic gas. The big new Australian telescopes like SkyMapper and the Australian SKA Pathfinder (ASKAP, see Australia’s SKA demonstrator already booked out) will give us an unprecedented view of how stars and gas in galaxies behave, he says. “Stars form where the gas is, so it’s hard to fully understand the process of star formation at a galactic level until you understand the gas processes. I think this is a real niche area which plays to the strengths of Square Kilometre Array (see Big science tackles the big questions) and ASKAP.”

PHOTO: A DEPICTION OF THE DISTRIBUTION OF MATTER IN AN OBJECT NEARLY TEN MILLION LIGHT YEARS ACROSS AND A THOUSAND TIMES THE MASS OF THE MILKY WAY. THOUSANDS OF THESE EXIST IN THE OBSERVABLE UNIVERSE. CREDIT: GREG POOLE, SWINBURNE UNIVERSITY OF TECHNOLOGY.

Swinburne Centre for Astrophysics and Supercomputing
Dr Darren Croton, Tel: +61 (3) 9214 5537, dcroton@swin.edu.au, astronomy.swin.edu.au/~dcroton/