Image of the week - In the beginning
Astronomers can “time travel” back into the universe’s early history using a number of “red shift” surveys that record objects in sections of the sky that are ever farther away—and therefore older, since their light travels billions of years to reach the Earth.
To help understand these observations, UC San Diego cosmologist Michael Norman and collaborators are using TeraGrid to crunch a simulation that uses the ENZO cosmology code, a code that can simulate the universe from first principles, starting near the Big Bang.
In work submitted to the Astrophysical Journal, the researchers have conducted the most detailed simulations ever of a region of the universe 500 megaparsecs across (more than 1.5 billion light years).
The size and detail of their results will be useful to other researchers involved in spatial mapping and simulated sky surveys.
The team’s detailed simulations required ENZO’s adaptive mesh refinement codes, which begin with a coarse grid spacing and then spawn more detailed (and more computationally demanding) subgrids in higher density regions.
“We achieved unprecedented detail by reaching seven levels of subgrids throughout the survey volume—something never done before—producing more than 400,000 subgrids, which we could only do thanks to the two large-memory TeraGrid systems,” says San Diego Supercomputer Center computational scientist Robert Harkness, who carried out about 500,000 processor hours of runs with astrophysicist Brian O’Shea of Los Alamos National Laboratory.
This story features in TeraGrid’s 2007 Science Highlights booklet, which was released at SC07.