| 39. | 2008 April 28 - May 1 | Boulder, Colorado |
| 38. | 2007 May 6-10 | University of Michigan, Ann Arbor, Michigan |
| 37. | 2006 June 25-29 | Saint Mary's University, Halifax, Nova Scotia |
| 36. | 2005 April 10-14 | Santa Barbara, California |
| 35. | 2004 April 20-23 | Cannes, France |
| 34. | 2003 May 4-7 | Cornell University, Ithaca, New York |
| 33. | 2002 Apr 21-24 | Timberline Lodge, Mt. Hood Oregon |
| 32. | 2001 Apr 22-25 | LPI, Houston, Texas |
| 31. | 2000 Apr 9-12 | Yosemite Valley, California |
| 30. | 1999 Apr 28 - May 1 | Estes Park, Colorado |
| 29. | 1998 Apr 1-3 | University of Virginia, Charlottesville, Virginia |
| 28. | 1997 Apr 14-16 | Lowell Observatory, Flagstaff, Arizona (Photo) |
| 27. | 1996 Apr 15-17 | U.S. Naval Observatory, Washington, D.C. (Photo) |
| 26. | 1995 Apr 24-26 | Yosemite Valley, California |
| 25. | 1994 Mar 27-29 | Texas A&M - Kingsville, Kingsville, Texas |
| 24. | 1993 May 13-15 | Santa Barbara, California |
| 23. | 1992 Jun 3-5 | Adler Planetarium, Chicago, Illinois |
| 22. | 1991 May 16-18 | Key Biscayne, Florida |
| 21. | 1990 Apr 25-27 | University of Texas at Austin |
| 20. | 1989 Aug 28-30 | Jet Propulsion Laboratory, Pasadena, CA |
| 19. | 1988 Jul 25-26 | National Bureau of Standards, Gaithersburg, MD |
| 18. | 1987 May 7-9 | Center for Astrophysics, Boston, MA |
| 17. | 1986 Apr 22-24 | Santa Barbara, California |
| 16. | 1985 Mar 28-29 | University of Texas, Austin, Texas |
| 15. | 1984 Jun 14-15 | Space Telescope Science Inst., Baltimore, MD |
| 14. | 1983 Jun 16-17 | University of Chicago, Chicago, IL |
| 13. | 1982 Jan 13-14 | University of Colorado, Boulder, CO |
| 12. | 1981 Mar 23-24 | University of Alabama, Tuscaloosa, AL |
| 11. | 1980 Jun 18-20 | University of Maryland, College Park, MD |
| 10. | 1979 Feb 28-Mar 2 | Stanford University, Palo Alto, California |
| 9. | 1978 Jan 11-13 | University of Texas, Austin, Texas |
| 8. | 1976 Dec 2-4 | University of North Carolina, Chapel Hill, NC |
| 7. | 1975 Dec 11-12 | Jet Propulsion Laboratory, Pasadena, California |
| 6. | 1974 Dec 8-10 | University of South Florida, Tampa, Florida |
| 5. | 1973 Nov 30-Dec 1 | University of Arizona, Tucson, Arizona |
| 4. | 1973 Jun 20-23 | University of Cincinatti, Cincinatti, Ohio |
| 3. | 1972 Mar 2-3 | University of Maryland, College Park, Maryland |
| 2. | 1970 Dec 7-9 | University of South Florida, Tampa, Florida |
| 1. | 1970 Jan 28-30 | University of Texas, Austin, Texas (Photo) |