College of Arts & Sciences
Distinguished Professor of Astronomy
The Ohio State University, Department of Astronomy
Originally from the Indian Wells Valley in California's Northern Mojave Desert, I attended Sherman E. Burroughs High School (Class of 1979) in Ridgecrest, California, otherwise known as the "Gateway to Death Valley", and home of the China Lake Naval Air Weapons Station (it was just NOTS, then NWC, when I was there). While at China Lake I was a member of the China Lake Astronomical Society, the folks who helped give me a start in Astronomy, and Boy Scout Troop 35, to whom I owe my abiding love of the outdoors. In 1979 I left the desert to attend Caltech, where I received my BS in Physics in 1983. At Caltech I was a member of Dabney House, and a sometime member of the infamous InfraRed Army. After graduation I headed north up the coast to UC Santa Cruz, where I received my PhD in Astronomy & Astrophysics in 1988. After a year at the University of Texas at Austin as a McDonald Fellow, I arrived at The Ohio State University as a postdoc in 1989, joining the faculty of the Astronomy Department in 1992 as an Assistant Professor. I have been a Full Professor of Astronomy at OSU since 2003. In 2021 I was named a College of Arts and Sciences College Distinguished Professor of Astronomy.
My primary research is concerned with the astrophysics of gaseous nebulae and active galactic nuclei as revealed through imaging and spectrophotometry at optical, UV, and infrared wavelengths with ground-based and space-based telescopes. I've followed three lines of inquiry. The first seeks to refine measurements of the masses of supermassive black holes in nearby active galaxies with the goal of calibrating the key scaling relations that will allow us to extend local methods out to cosmological distances. The second used the Hubble and Chandra space telescopes to study how local active nuclei are fed by gas from their host galaxies, and how that activity in turn feeds back upon their hosts. The third is to use precision spectrophotometry to measure direct and empirical elemental gas-phase abundances in star formation regions to trace the chemical evolution history of galaxies from the Big Bang to the present.
At home in the Milky Way, I have joined in the search for planets around other stars. I am part of the MicroFUN collaboration based at OSU that has organized a worldwide network of amateur and professional telescopes to make coordinated observations to search for extrasolar planetary systems using gravitational microlensing. I have also been engaged searches for and detailed follow-up studies of transiting exoplanets, through the KELT North, KELT South, and DEMONEXT projects, as well as exploring new techniques using adaptive optics.
Research requires the best data, and to collect that data I have devoted much of my career to the the design and construction of advanced astronomical instruments, including development of software for image processing, spectral analysis, and instrument control & data acquisition. Instruments I have helped develop are in regular use at the MDM Observatory in Arizona and on the SMARTS telescopes in Chile. My biggest instrumentation projects to date are the twe Multi-Object Double Spectrographs (MODS) we built for the Large Binocular Telescope on Mt. Graham in Arizona, and the robotic Focal Plane Systems for the SDSS-V project.