In the outskirts of galaxies live dense clusters of stars, known as “globular clusters” due to their spheroidal appearance. These clusters feature tens of thousands of stars packed into a distance similar to that between our sun and the next nearest star to us. Globular clusters are extremely exotic environments compared to our sun’s local galactic neighborhood, and the precise nature of how they are formed is still a mystery.
I’m a member of the SAGES collaboration, led by Professor Jean Brodie at UC Santa Cruz. Using cutting-edge observatories, we study globular cluster systems of nearby galaxies. Because these clusters are so dense, they are extremely bright, and so they can be easily observed with modern telescopes far out in a galaxy’s halo, when the galaxy’s diffuse starlight is far too faint to see.
The SAGES collaboration is currently conducting the SLUGGS Survey, a combination photometric and spectroscopic survey of the globular cluster systems of 25 nearby galaxies. We use wide-field imaging from the Subaru and CFHT observatories to study the full extent of globular cluster systems around these galaxies, then use spectroscopy from the Keck observatory for in-depth follow-up of the brightest globular clusters seen in the imaging data. Combining these two powerful methods enables us to understand how these globular cluster systems assembled around these galaxies, giving us a powerful window into just how these exotic star clusters slot into the puzzle of galaxy evolution.