Benjamin J. Gibson

Graduate Student Research Assistant
University of Utah Astronomy

Welcome! I am Ben Gibson, a fifth year grad student at the U! I am currently working on a project to determine the chemistry, kinematics, and star formation history of the stellar populations in the Andromeda Galaxy (M31)! I was born and raised in Charlotte, NC and did my undergraduate studies at Florida State University.

I currently serve as the Chair of my department's Graduate Student Advisory Committee, which plans social events for our students, organizes a Peer Mentor Program, the Graduate Research Seminar, and has recently advocated for and received improved health care, fairer testing standards, and better wages for grads in our department and around campus!


I am broadly interested in the structure and evolution of disk galaxies, especially the origin of the bimodal distribution of certain elements in the Milky Way's disk. I am also interested in the interplay between a group of stars with similar properties (called a stellar population), and their combined, or integrated, light.

Galactic Structure

The distribution of mass (namely stars and gas, but also dark matter) in a galaxy contains a wealth of knowledge about its past. For example, if a galaxy has a highly structured disk (ie a strong bar and spiral arms), it is less likely to have had a recent significant merger to mix everything up.

The Alpha Bimodality

The Milky Way's disk is split into two components. One is made up of generally older stars that have less circular orbits that take them further from the galaxy's midplane. This is generally called the thick disk. The other component, naturally called the thin disk, is made up of generally younger stars on rather circular orbits much more confined to the midplane. This pattern exists in many disk galaxies, however in the Milky Way, this distinction goes further. The chemical makeup of these stars are rather different. The origin of this distinction is likely a result of the Milky Way's merger history, but we are not sure how common it is in other galaxies.

Integrated Light

In order to find this bimodality in other galaxies, we have to observe the integrated light of its stars. Furthermore, we have to be able to differentiate between multiple distinct stellar populations occupying the same region of a galaxy. I am currently working on methods to do this for the Andromeda Galaxy, using data obtained from APOGEE, part of SDSS. Establishing the prevalence of this structure throughout the universe is essential towards building more accurate, versatile models of galactic evolution.


Gibson, Benjamin J.; Zasowski, Gail; Seth, Anil; ...; et al., 2023, The Chemodynamics of the Stellar Populations in M31 from APOGEE Integrated Light Spectroscopy, Astrophysical Journal, 952, 23 (arXiv:2304.09901)

The primary results from this paper are shown left. They are maps of the average kinematics, chemical composition, and age of the stellar populations in the disk and bulge of M31.

Wainer, Tobin M.; Zasowski, Gail; ...; Gibson, Benjamin J.; et al., 2023, Catalog of Integrated-light Star Cluster Light Curves in TESS, Astronomical Journal, 166, 106 (arXiv:2307.09510)

Dey, Arjun; ...; Gibson, Benjamin J.; ...; et al., 2023, RomAndromeda: The Roman Survey of the Andromeda Halo, (arXiv:2306.12302)

Abdurro’uf,..., Gibson, Benjamin J., et al., 2022, The Seventeenth Data Release of the Sloan Digital Sky Surveys: Complete Release of MaNGA, MaStar, and APOGEE-2 Data, Astrophys J Suppl Ser, 259, 35 (arXiv:2112.02026)


Outside of research, I have several hobbies, many of which take advantage of the beautiful locale around Salt Lake City.

  • Backpacking
  • Rock Climbing
  • Golfing
  • Cooking
  • Photography
  • Music
  • Sports

Contact Me

Email: ben DOT gibson AT

Address: 115 S 1400 E, Salt Lake City, UT. 84112

Instagram: @benjamingibsonphotography