Researchers search for galactic answers to origins of space

By ANGELA HAYES

A Pitt professor teamed up with a researcher in Germany to search for missing galaxies in… A Pitt professor teamed up with a researcher in Germany to search for missing galaxies in high-speed galactic clouds. The search, however, came up empty.

“This research is important because it addresses how galaxies formed and evolved, which is currently one of the big questions that astrophysicists are trying to answer,” said Regina Schulte-Ladbeck, professor of physics and astronomy.

Schulte-Ladbeck and Ulrich Hopp – from Munich, Germany – presented the results of their findings at the meeting of the American Astronomical Society in Washington.

In the paper, they concluded that hundreds of dwarf satellites, a smaller kind of galaxy that contains only a few billion stars, have been hiding from observers. Schuhlte-Ladbeck said that now the bulk of the work is done and that even the stars’ absence will be helpful in constraining some possible solutions that other astronomers are coming up with.

According to Schulte-Ladbeck, cosmological simulations of the Big Bang predict that every giant galaxy in today’s universe should be surrounded by a few hundred building blocks in the form of dwarf galaxies. However, in the vicinity of the Milky Way galaxy only about 50 dwarf galaxies are known.

“This dramatic discrepancy between predicted and observed dwarf satellite abundances has become known as the substructure problem of cosmology,” Schulte-Ladbeck said.

She suggested that the easy way out of the problem would be to find that the dwarf galaxies exist but have been overlooked by observers.

David Turnshek, who teaches the class Galaxies and Cosmology, said that the results of Schulte-Ladbeck’s search will have an impact on other astronomers’ research across the world. The research could also impact the theories taught in astronomy classes.

“The fundamental question is, ‘what is the nature of those clouds?'” he said. “It’s an open question.”

Turnshek said that in today’s educational environment, Pitt’s approach is to put the two sciences, physics and astronomy, together.

“You can’t advance if you don’t combine the laws of physics with astronomy,” he said.

George Gatewood, who teaches the class Stars, Galaxies and the Cosmos at Pitt, said that Schulte-Ladbeck’s findings “peaked his interest.”

He takes his classes to the Allegheny Conservatory in Riverview Park, Pa., where 1,200 students per year visit and learn how to use telescopes.

The Allegheny Conservatory, which is funded by NASA and the National Science Foundation, is home to the second largest refracting telescope in the United States. Gatewood said he believes that the conservatory’s access to college students is unique.

“No other large university has a large research observatory so close to it,” he said.

A refracting telescope is a telescope that primarily works off of lenses, as opposed to reflecting telescopes, which primarily use mirrors.