Rate My Professor Ian Crossfield

Ian J. M. Crossfield is an Associate Professor of Physics and Astronomy at the University of Kansas, where he joined as Assistant Professor in 2020 and was promoted to Associate Professor in 2023. He leads the KU ExoLab, a research group dedicated to the discovery and characterization of nearby planetary systems. His research specializes in exoplanet formation, composition, detection, and characterization, studying extrasolar planets and their host stars using photometry and high-resolution spectroscopy from ground- and space-based observatories. As Principal Investigator or lead author, Crossfield has obtained over 1200 hours of observing time on Hubble and Spitzer space telescopes, observed more than 5000 targets using NASA's Kepler and TESS missions, over 700 hours on 6-10m ground-based telescopes including Keck, Gemini, VLT, Subaru, LBT, Magellan, and MMT, and more than 1000 hours on 2-5m telescopes such as IRTF, WIYN, APF, Shane, and NTT.

Crossfield received his Ph.D. in Astrophysics from the University of California, Los Angeles in 2012 with a dissertation titled 'Infrared Observations of Exoplanet Atmospheres,' an M.S. in Astrophysics from UCLA in 2009, and a B.S. in Physics magna cum laude from the University of California, Irvine in 2004. His career trajectory includes Assistant Professor at the Massachusetts Institute of Technology (2017-2020), NASA Sagan Postdoctoral Fellow at the Jet Propulsion Laboratory (2014-2016) and Max Planck Institute for Astronomy (2012-2014), and earlier roles at UCLA and JPL. Among his honors are the NASA Sagan Fellowship (2014), Kavli Frontiers of Science Fellowship (2015), AAS Rodger Doxsey Prize (2013), two AAS Chambliss Student Achievement Awards (2009, 2010), and selection as Chair of the NASA Exoplanet Program Analysis Group Executive Committee (2025 onward). Key publications include 'A Nearby M Star With Three Transiting Super-Earths Discovered by K2' (ApJ, 2015), 'Observations of Exoplanet Atmospheres' (PASP, 2015), 'GJ 1252b: A Hot Terrestrial Super-Earth with No Atmosphere' (ApJL, 2022), 'Volatile-to-sulfur Ratios Can Recover a Gas Giant’s Accretion History' (ApJL, 2023), and 'Mapping the SO2 Shoreline in Gas Giant Exoplanets' (AJ, 2025). His work has advanced exoplanet atmospheric studies and mentored students earning NSF Graduate Research Fellowships.