Faculty Sponsor

Bruce Hrivnak


Arts and Sciences


Physics and Astronomy

Presentation Type

Poster Presentation

Symposium Date

Summer 7-23-2021


As a sun-like star nears the end of its life, the star will eventually eject its outer gaseous layers, while the core shrinks and heats. The product of this process is a glowing gaseous planetary nebula, which will eventually fade away, leaving the hot inner core known as a white dwarf. Our research group has been studying light variations in the preceding process of a planetary nebula known as a protoplanetary nebula (PPNe), where the core is not hot enough to make the gas glow. Our previous observational studies have been focused on cooler PPNe, which have shown more distinct periodicity in their variations (30-160 days). Hotter, more evolved PPNe have shown variation on a shorter timescale, but it is unclear if it is periodic. This summer, I am intensively observing one PPNe, IRAS 19200+3457. A previous observational study was conducted at Valparaiso University, showing that it seemed to vary in cyclical behavior in periods of a few days or less. This research was supported by the National Science Foundation.