February 4, 2002 Powerful new supercomputer provides high-speed platform for research in planetary physics and astrophysics By Tim Stephens UCSC researchers have installed a new supercomputer that ranks among the 100 fastest computers in the world. The computer will be used for research in planetary physics and astrophysics by scientists in the Departments of Earth Sciences, Physics, and Astronomy and Astrophysics. A snapshot of the three-dimensional structure of Earth's magnetic field from a computer simulation of the "geodynamo"--the motion of the Earth's fluid outer core that generates the magnetic field. Magnetic field lines are blue where the field is directed inward and yellow where directed outward. The rotation axis of the model Earth is vertical and through the center. The field lines are drawn out to two Earth radii. Image: Gary Glatzmaier Research in these fields often involves computer simulations of complex physical phenomena, such as supernova explosions, galaxy formation, and the fluid dynamics of the interiors of stars and planets. UCSC researchers sometimes run their simulations on powerful supercomputers at other institutions, such as Lawrence Berkeley National Laboratory. But having comparable supercomputing resources on campus will be a tremendous advantage, said Gary Glatzmaier, professor of Earth sciences and director of UCSC's Center for the Origin, Dynamics, and Evolution of Planets (CODEP) within the Institute of Geophysics and Planetary Physics. "We won't have to compete for computer time with researchers at other institutions, and we will be able to involve more graduate students in these projects," Glatzmaier said. Most of the funding for the new computer was provided by a $538,000 grant from the National Science Foundation. In addition to Glatzmaier, the principal investigators who will be using the new computer are Erik Asphaug, assistant professor of Earth sciences; Stanley Flatté, professor of physics; Joel Primack, professor of physics; and Stan Woosley, professor and chair of astronomy and astrophysics. Woosley noted that computer simulation has emerged in recent years as a "third branch of science," complementing the traditional approaches of observation and theory. "I think there is a changing paradigm in science as a result of the increasing use of computer simulations," Woosley said. "Simulation involves aspects of both the theoretical and observational approaches. You use theory to create a mathematical model of some phenomenon, but then you have to analyze the data generated by running the model on a computer. And the ultimate test is to compare the output of the simulation against observational data." Running the simulations requires extremely powerful computers. UCSC's new supercomputer is a "Beowulf cluster," a type of high-performance, massively parallel computer built from standard processors linked together by a high-speed network. UCSC's new Beowulf cluster, built by RackSaver Inc., consists of 132 nodes configured with 264 AMD Athlon 1.4 GHz processors, with 132 gigabytes of memory and nearly 8 terabytes of storage. The system's performance on a standard industry benchmark exceeded 300 gigaflops (300 billion calculations per second), placing it in the 99th position on the Top 500 list of supercomputer sites. This is the third Beowulf cluster installed by researchers in UCSC's Division of Natural Sciences, and by far the most powerful. The two smaller computers, a 16-processor cluster used by Woosley for astrophysics research and a 32-processor cluster used by Asphaug and Glatzmaier, convinced the researchers that this type of system could meet their needs at a reasonable cost. "The small ones are getting a lot of use, but the new 264-processor computer is much more powerful. It's a pretty impressive machine," Glatzmaier said. Glatzmaier will use the new computer to run three-dimensional simulations of convection and magnetic-field generation in the fluid interiors of planets and stars. He has produced the first self-consistent simulation of the Earth's magnetic field, including spontaneous dipole reversals like those observed in the paleomagnetic record. Asphaug uses computer simulations to study collisions of asteroids and planets. His simulations have shown, for example, how the Moon may have formed as a result of a collision between the early Earth and another planetary body about the size of Mars. Woosley studies supernovae, the massive explosions of dying stars, and gamma ray bursts, mysterious blasts of intense radiation. He has developed some of the most sophisticated computer simulations of supernova explosions and gamma-ray bursts. Woosley is director of the Center for Supernova Research, funded by the Department of Energy and headquartered at UCSC. Primack develops high-resolution cosmological models to study the formation and evolution of large-scale structure in the early universe. His research explores such questions as the origins of galaxies and the nature of the "dark matter" that composes at least 90 percent of the universe. Flatté studies wave propagation in random media, such as electromagnetic waves propagating through a turbulent atmosphere and sound waves propagating through the ocean. In addition to supporting these research projects, the computer will be used to train students at both the undergraduate and graduate levels in effective parallel programming techniques and in the application of these techniques to problems in their respective disciplines. Return to Front Page