Keck Observatory Donor Salon Talk: A New Tool to Map Entire Galaxies

Staff Astronomer

Dr. Rosalie McGurk 

W. M. Keck Observatory

All the popular images of galaxies, while beautiful, do not provide adequate information for astronomers to measure the galaxies’ inherent properties, like the dynamics and composition of their stars and gases.  Instead, astronomers study the universe by doing spectroscopy, or spreading light into its component wavelengths/colors. Spectroscopy allows us to see what chemical elements make up stars and galaxies and to measure the velocities of stars and galaxies.

Unfortunately, most current spectroscopic instruments used by astronomers only show a small part of local galaxies, limiting their understanding of them. With the Keck Cosmic Web Imager, one of the newest instruments at Keck Observatory, astronomers can now look at an entire galaxy with great detail in one observation. This will allow astronomers to measure the inherent properties of galaxies such as where their chemical elements are located and how the galaxies are moving.

Dr. McGurk will introduce spectroscopy, share how integral field spectrographs work, and provide astronomical examples which include some from her own research.

W. M. Keck Observatory wishes to offer our deepest gratitude to our Astronomy Talk Series sponsors, Rob and Terry Ryan.