KU ExoLab

About Me:

Prof. Crossfield leads the KU ExoLab, a research group dedicated to the discovery and characterization of nearby planetary systems.
I am an Assistant Professor of Physics and Astronomy working at Kansas University's Department of Physics and Astronomy. My interests lie in exoplanet formation, composition, detection, and characterization, and the development of instrumentation to further those pursuits. I am currently studying extrasolar planets using both photometry and high-resolution spectroscopy from the ground and space. I have worked all over: as an assistant professor in the MIT Kavli Institute and associated Department of Physics, as an adjunct professor and postdoctoral fellow at the UC Santa Cruz Astronomy Department, for two years at UA's Lunar and Planetary Laboratory in Tucson, for two years at the MPIA in Heidelberg, Germany and for three years at the Jet Propulsion Laboratory. I received my doctorate from UCLA. I once maintained an online repository of useful Python computing tools (which urgently needs to be moved to GitHub).

White dwarf planet
Artist's impression of the new white dwarf planet.
(From NASA).

Recent Results:

2020 Sep: So-called "White Dwarfs" are the dying embers of former stars like our sun. Known for over a century, these small, dense objects are intrinsically very faint and so much tougher to study than larger, hotter, brighter stars. In a first-of-its-kind discovery, our research group was part of the team that just discovered the first known planet orbiting one of these white dwarfs. The planet is a large, cool, Jupiter-like gas giant with a "year" (the time it takes it to orbit once around the white dwarf) of just over 30 hours. Read more about it here at KU and at at NASA.

2019 Jan: Low-mass M dwarfs represent the most common outcome of star formation, but their complex atmospheres (filled with molecules such as H2O) hinder detailed studies of their composition and initial formation. The measurement of isotopic ratios is a key tool that has been used to unlock the formation of our Solar System, the Sun, and the nuclear processes within more massive stars, and our team applied the study of 12C16O, 13C16O, and 12C18O for the first time to any dwarf stars beyond the Solar system. Since the stars are fully convective, their atmospheres should be uniformly mixed and so our observations directly probe the conditions and composition of natal gas making up these stars. These measurements poze a puzzle for models of how our Milky Way galaxy, and stars in the Solar neighborhood, formed; we intend for our novel isotopic analysis to open a new window onto studies of Galactic evolution, stellar populations, and individual systems. You can read about our results, published in ApJ Letters, online here.




IJMC Photo
IJMC

Publications, Proceedings, and Talks

Curriculum Vitae

Travel

Contact Information:

Ian J. M. Crossfield
Department of Physics and Astronomy
Kansas University
1082 Malott,1251 Wescoe Hall Dr.
Lawrence, KS 66045