Sarah Gallagher, Professor

Sarah Gallagher

Contact Information

Office: PAB 205
Tel:  (519) 661-2111 x86707

Personal web page 
Western Space 

Research Areas

Extragalactic astrophysics: active galaxies and quasars, compact galaxy groups 
Philosophy of astrophysics

Research Interests

I am interested in how supermassive black holes in the centres of distant galaxies grow and the impacts of this growth on their environments. To address these questions, I use telescopes from the radio to X-rays, on the ground and in space. Computer simulations and machine-learning algorithms are also important tools for my research.



  1. Dewsnap, C., Barmby, P., Gallagher, S. C., Urry, C. M., Ghosh, A., and Powell, M. C., “GALFIT-ing AGN Host Galaxies in COSMOS: HST versus Subaru”, The Astrophysical Journal, vol. 944, no. 2, 2023. doi:10.3847/1538-4357/ac9400.
  2. Choi, H., Leighly, K. M., Terndrup, D. M., Dabbieri, C., Gallagher, S. C., and Richards, G. T., “The Physical Properties of Low-redshift FeLoBAL Quasars. I. Spectral-synthesis Analysis of the Broad Absorption-line (BAL) Outflows Using SimBAL”, The Astrophysical Journal, vol. 937, no. 2, 2022. doi:10.3847/1538-4357/ac61d9.
  3. Rivera, A. B., Richards, G. T., Gallagher, S. C., et al., "Exploring Changes in Quasar Spectral Energy Distributions across C IV Parameter Space," The Astrophysical Journal, Volume 931, Issue 2, id.154, 19 pp. doi:10.3847/1538-4357/ac6a5d
  4. Smeenk, C. & Gallagher, S.C., "Validating the Universe in a Box", Philosophy of Science 87 (5):1221-1233 (2020), DOI:10.1086/710627

[Complete Publications Listing (Scopus)]

[Complete Publications Listing (NASA ADS)]


Astronomy 3303: Galaxies

Astronomy 9720: Galaxies


  • Outstanding Science Alumni Award, Eberly College of Science, Penn State, 2023
  • Purvis Memorial Award, SCI Canada, 2021
  • Faculty Scholar Award, Western University, 2016-2018
  • Faculty of Science Outreach Award, 2010
  • Ontario Ministry of Research & Innovation Early Researcher Award, 2010-2014
  • International Union of Pure and Applied Physics Commission on Astrophysics Young Physicist Prize (Honorable Mention), 2008
  • Spitzer Fellowship, 2003-2006

Professional Activities

  • Director, Institute for Earth and Space Exploration, Western University, 2021-present
  • Science Advisor to the President, Canadian Space Agency, 2018-2022
  • Mauna Kea Spectroscopic Explorer Science Team, member, 2014-present
  • Joint Committee on Space Astronomy, member, 2015-2017
  • Canadian Astronomical Society (CASCA) Board, Directory, 2014-2017
  • Canadian Time Allocation Committee (CanTAC), chair, 2013-2014, member, 2011-2014
  • Space Telescope User's Committee, 2009-2011
  • Local Organizing Committee, CASCA 2011, co-chair, 2011
  • Canadian Astronomical Society (CASCA), full member
  • American Astronomical Society (AAS), full member