UA Public Night to Feature Saturn Viewing, Talk on Galaxies

TUSCALOOSA, Ala. – A talk on the Milky Way’s nature and outside galaxies, followed by an opportunity to peer at the moon and Saturn through a University of Alabama research telescope, highlights the April 27 public sky viewing on campus.

Dr. Gene Byrd, professor of astronomy at UA, will give a talk, “Spiral Arms in Disk Galaxies: Beautiful Patterns and Dark Matter,” beginning at 8 p.m in Gallalee Hall, room 227. Visitors may then, weather permitting, climb the stairs to the building’s roof and use the 16-inch research grade reflector telescope for a close look at Saturn and the moon. Astronomy graduate student Anna Manning and Byrd will conduct the viewing.

The free event, which is open to the public, is hosted by UA’s department of physics and astronomy. Gallalee Hall is located near the northwest corner of University Boulevard and Hackberry Lane on the UA campus. For more information, phone 205/348-5050 or see http://www.astr.ua.edu/Public.html.

In addition to discussing the galaxies’ elegant spiral patterns and the evidence for their containing dark matter, Byrd will discuss the puzzle behind a galaxy with “backward” arms.

This galaxy, known as NGC 4622, lies 111 million light years away in the constellation Centaurus. It has long been believed that most spiral arms seen in galaxies are trailing, meaning they wind outward opposite the direction of rotation of the disk material, something like what one sees while stirring cream into a cup of coffee. A leading arm does the opposite, opening outward into the same direction as the rotation of the galaxy’s disk.

In recent years Byrd and his colleagues, using data from time awarded them for Hubble Space Telescope use, determined that this galaxy’s two outer arms were leading, not trailing as do most galaxies’ arms. The researchers have theorized that the unusualness resulted from the galaxy having earlier consumed a smaller galaxy.

The department of physics and astronomy is part of the College of Arts and Sciences, the University’s largest division and the largest liberal arts college in the state. Students from the College have won numerous national awards including Rhodes Scholarships, Goldwater Scholarships and memberships on the “USA Today” Academic All American Teams.