RR Lyrae Stars and Stellar Evolution in the Globular Cluster M15

Here is a blinking gif of M15 - how many variable stars can you find?

This is an observing project I conducted as an undergraduate at the University of Rochester with my classmate Bo Peng for our advanced laboratory course. We observed the globular cluster M15 with the 24” telescope at the C.E.K. Mees Observatory. We identified variable stars in the cluster and performed photometry on the stars to compute lightcurves for the variables, as well as an HR diagram M15 as a whole. We used the derived periods of the variables, along with observations of the star RR Lyrae, to estimate the distance to M15.