As an undergraduate at MIT, I worked on data from the SAS-3 X-ray satellite and was an operator. After my Ph.D. work (on quasar evolution), I was a Fellow at the Space Telescope Science Institute for two years. I then worked on the Extreme Ultraviolet Explorer Project for 8 years, in charge of the scientific data analysis system. Since 1993, I have been the instrument calibration scientist for the Chandra High Energy Transmission Grating Spectrometer, also involved in cross-calibration with other X-ray satellites.

I am currently working on high resolution X-ray and optical images of quasar jets, high resolution X-ray spectroscopy of active galactic nuclei and neutron star atmospheres, and X-ray spectroscopy of the X-ray binary SS 433. I am also developing a laboratory for testing techniques and prototype instrumentation that can be used to measure linear X-ray polarization in the soft X-ray band.