Binary Stars in Planetary Nebulae

Planetary nebulae and their abnormal shapes have often been the topic of discussion among astronomers. Ideas for the cause of those shapes have bounced from a single star system with either extreme magnetic fields or rotation, to more recently a binary star system. This research explores the binary star theory, and has aided in showing that binary star systems are both theoretically likely and observationally common. The goal of this research is to identify binary systems in planetary nebulae out of a range of target objects, and when identified, to attempt to learn more about the binary system itself (i.e. type of companion, orbital period, etc.). One method for identifying binary systems is to look for changes in brightness caused by a close companion star. Work this summer used a program called AstroImageJ in order to measure the change in brightness of the target star and begin this identification process. We have been able to confirm two binary systems. One of which we determined to be a double degenerate binary system, consisting of two white dwarf or pre-white dwarf stars, and the other to be an eclipsing binary system. The hope is to continue identifying systems as the project continues