* Astronomy

David Fisher, an astronomy graduate student at The University of Texas at Austin, is making important contributions to the future understanding of galaxy evolution by studying the different types of bulges at the hearts of nearby spiral galaxies. This work is being presented this week at the 207th meeting of the American Astronomical Society in Seattle, Washington.
A bulge is a concentration of stars in the center of a spiral galaxy. In recent years, evidence has shown that there are two types of bulges— the so-called “classical bulges” and “pseudobulges.”
Studying these bulges and finding out how many nearby galaxies have the different types is important.

"We believe that the formation of these two types of bulges is dramatically different" - David Fisher.

Such findings could be important to theories of galaxy formation.
A classical bulge is a mostly featureless, round ball of stars. A pseudobulge, on the other hand, “looks very much like the (galaxy’s) outer disk, with a spiral structure. It can have a bar, and can be very flat, instead of round.”

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