Megan Donahue studies clusters of galaxies. Cluster evolution tells us about the matter density of the universe, because the formation of galaxy clusters is governed by gravitational physics. She pays particular attention to how clusters are found, because any bias in finding clusters can lead to a bias in our conclusions about them. She also studies the metallicity, distribution, and physics of intergalactic gas. Is this really where most of the baryons are hiding? Her work includes models and observational tests of cooling flows in the gas within clusters. Strange things are afoot in cluster cores and she would like to sort it out.
Professor Donahue was named a Fellow of the American Physical Society in October 2016 for "advanced cosmological observations and analyses of galaxy clusters, and of the relationship between the thermodynamic state of circumgalactic gas around massive galaxies, the triggering of active galactic nucleus feedback, and the regulation of star formation in galaxies" after nomination by the APS Division of Astrophysics.
Professor Donahue is currently serving as President of the American Astronomical Society.