- Star clusters - formation and dynamics.
- Optical studies of orbital debris.
- History of Astronomy.
The University of Michigan's former Lamont-Hussey Observatory on Naval Hill in Bloemfontein, South Africa. The Observatory was founded in 1928 with a 27-inch visual refractor, the largest in the Southern Hemisphere. Observing ended in 1971. The telescope was removed and the 27-inch lens returned to Michigan. Until very recently the Observatory building was used as a performing arts theater. Photographed in October 2008 by the author.