newsn
Science;|;DOI: 10.1145/1735223.1735230
Jeff;Kanipe
modeling the
astronomical
Advances in computer technology have changed
the way astronomers see and study the universe.
AsTroNoMers oNCe LearNed everything they knew about the universe from telescopes, spectroscopes, and other optical instruments. Today, one of the most important items in an astronomer’s toolbox
is the computer. Galaxy and star formation, supernova explosions, even
the origins of the universe—all can be
modeled and manipulated to an incredible degree using computers, both
powerful mainframes and desktop
models. What follows are just a few examples of computer applications that
are helping scientists paint bold, new
pictures of the cosmos.
smashing Galaxies
illustration courtesy of eso/l. calçada
In the early years of the 20th century,
astronomers believed that collisions
between galaxies were so rare that
few, if any, examples might ever be observed. Even in clusters, galaxies are
small compared to the vast distances
between them, therefore an encounter
was deemed unlikely. This mind set
quickly shifted, however, once more extensive photographic surveys of the sky
revealed that some galaxies appeared
to be peculiar amalgams of both spiral-shaped galaxies and spheroidal galax-
Gliese 667 c and a pair of stars that were discovered by the high accuracy Radial Velocity Planet
searcher, the spectrograph for eso’s 3.6-meter telescope at the La silla observatory in chile.
ies. Most of these disturbed specimens
could only be explained as products of
mergers with other galaxies.
Astronomer and mathematician
Alar Toomre, of the Massachusetts In-
stitute of Technology, and his brother
Jüri, of the University of Colorado,
Boulder, conducted some of the first
computer simulations of galaxy inter-
actions in the early 1970s. They de-
signed numerical programs that could
determine the trajectories of a number
of test particles, or N-point masses, in
which only gravitational interactions
are considered. Such programs were
run on state-of-the-art mainframes
