| 2015– | Robert Wheeler Willson Professor of Applied Astronomy |
|---|---|
| 1999–2015 | Professor, Harvard University Astronomy Department |
| 1995– | Research Associate, Smithsonian Astrophysical Observatory |
| 2009–2010 | Scholar–in–Residence, WGBH Boston (consultant role) |
| 2008–2009 | Scholar–in–Residence, WGBH Boston (sabbatical) |
| 2005–2008 | Founding Director, Harvard Initiative in Innovative Computing |
| 2002–2010 | Principal Investigator, The COMPLETE Survey of Star–Forming Regions |
| 2001–2002 | Visiting Professor, Yale University Astronomy Department (sabbatical) |
| 1996–1999 | Associate Professor, Harvard University Astronomy Department |
| 1995–1997 | Head Tutor, Harvard University Astronomy Department |
| 1992–1996 | Assistant Professor, Harvard University Astronomy Department |
| 1989–1992 | Post–doctoral Fellow, University of California, Berkeley |
| 1984–1989 | Research Assistant, Harvard–Smithsonian Center for Astrophysics |
| 1983 | Summer Fellow, NASA–Goddard Institute for Space Studies |