Computer simulations of galaxies growing over billions of
years have revealed a likely scenario for how they feed: a cosmic version of
swirly straws.
The results show that cold gas -- fuel for stars -- spirals
into the cores of galaxies along filaments, rapidly making its way to their
"guts." Once there, the gas is converted into new stars, and the
galaxies bulk up in mass.
"Galaxy formation is really chaotic," said Kyle
Stewart, lead author of the new study appearing in the May 20th issue of the
Astrophysical Journal. "It took us several hundred computer processors,
over months of time, to simulate and learn more about how this process works."
Stewart, who is now at the California Baptist University in Riverside, Calif.,
completed the majority of this work while at NASA's Jet Propulsion Laboratory
in Pasadena, Calif.