A star is found

Agnes Kim, assistant professor of astrophysics, is responsible for a discovery that is out of this world.  

Kim’s astronomical research has led to the discovery of Kepler DBV, a white dwarf star. Kim is the sole researcher in the world to gather and analyze conditions on the softly glowing blue star.

“I am proud that this professor is associated with Georgia College, this is an amazing find and she makes the university as a whole look accomplished,” sophomore history major Ashley Gibson said.

Kim’s discovery stems from a passion for astronomy. She found a desire to study the stars as a child.

“I always enjoyed these astronomy books we had lying around our house,” Kim said.

Though her desires took her away from astronomy when she had the dreams of studying particle physics at the European Organization for Nuclear Research in Geneva, an undergraduate project on white dwarf stars shifted her plans. She was studying meteorology at the time but her love of the field of astronomy brought her back to it.

Kim began her research on white dwarfs while working as a professor at GC. White dwarf stars are roughly the size of Earth but incredibly dense. The likelihood of finding this particular star was exceedingly rare. The process of finding white dwarfs is chancy, at best.

“We use a satellite; my colleagues in Belgium have it fixed on a certain section of sky and then from there we analyze the section to try to pinpoint stars or planets or other notable finds,” Kim said. “The probability that there would be a white dwarf in this section was next to none.”

To date there are few known dwarf stars, and this one is unique even among those. Kepler DBV is hot, five times hotter than the sun at approximately 29,000 degrees Kelvin. Kim found this out through her extensive research in the last two months. In her lab she crunches numbers with her students to study the star’s pulsations. Kim describes measuring the dwarf’s pulsations as, “ringing a bell behind a screen, even though you can’t see the bell you can tell the pitch and size of the bell, it is similar with the pulsations given off by the white dwarf, the pulsations can tell us a lot about the star.”

Kim knew this star was hotter because its pulsations gave off a different reading from dwarfs of similar consistency, suggesting a difference in its make-up. She uses computers and an evolution code for white dwarfs to determine pressure, density and temperatures inside the star through interpreting its pulsations.

Her students help her extensively in her research, taking figures and interpreting data.

“Dr. Kim is always enthusiastic about her work with astroseismology,” junior physics major Michael Rodriquez said.

Kim and her students hope to use the data gathered from Kepler DBV and other white dwarfs to interpret how white dwarfs are formed and use the information to gauge the age of this galaxy as well as others. She also plans on publishing more of her findings and sharing the information she has gathered at conferences and with the academic community.