Anil Seth, Associate Professor of Physics and Astronomy, fell in love with astronomy in high school in Lincoln, Nebraska. Now, when he isn’t teaching classes at the U, or mentoring graduate students, he spends his time searching for black holes at the centers of low-mass galaxies.
“I still get excited by the fact that we can look through a telescope and find things in the universe that can tell us how and why we got here,” says Seth. “As I’m doing my research I often feel like an archaeologist, too, because I’m looking for clues to tell me what happened.”
His work is funded by NASA and the National Science Foundation. He has over 100 research publications in peer-reviewed journals.
For every large galaxy like the Milky Way there are many smaller galaxies. Some of these smaller galaxies are satellites that orbit around the larger galaxies, and they can be torn apart by the bigger galaxy’s gravity. This process takes millions of years.
“These are the galaxies that I study,” says Seth. “For example, orbiting around our Milky Way galaxy are companion dwarf galaxies called the Magellanic Clouds. If you go to the Southern Hemisphere, you can see them with the naked eye. What I’m trying to find out through my work is whether these low-mass dwarf galaxies have black holes.”
Finding a black hole requires observations with cutting-edge telescopes to monitor the effect of gravity on the motions of the stars that surround it. Seth had been studying black holes for nearly a decade when his research paid off with a big discovery. In 2014, he and his collaborators found the first black hole at the center of an “ultra-compact dwarf” galaxy.
“It was pretty exciting for my team and me,” says Seth. “Once we were able to track the speed of the stars orbiting in the galaxy, we were able to prove the presence of a black hole. This particular one is 21 million times the mass of our sun, or 15 percent of the total mass of the galaxy itself.”
In addition to his research, Seth wants to make sure the Physics and Astronomy Department is able to continue its community outreach efforts. The department travels to schools across Utah, providing demonstrations and teaching kids about the universe.
In addition, “star parties” are open to the public Wednesday evenings (weather and nighttime skies permitting) at the Physics and Astronomy Department’s observatory on campus. For details, see http://web.utah.edu/astro/.
“The star parties and our public lectures are such a great way for us to connect with the community,” said Seth. “We’re always looking for ways to get people interested in astronomy.”