The Smithsonian Astrophysical Observatory has a Visiting Scientist and Visiting Student Program to expand scholarly exchange in atomic and molecular physics; infrared, optical, radio, and X-ray astronomy; planetary sciences; geophysics; solar and stellar physics; and theoretical astrophysics. Visits can vary from a few days to several weeks or months and, in some cases, last up to a year. This program annually attracts many international and national visitors.

Stipend support varies with the length of the visit and the amount of support being provided by the visitor's home institution, or by fellowships such as a Guggenheim or from NATO, etc. Application to the program is made by directly contacting a member of the research staff to request support. Awards are dependent upon availability of funding. Information about SAO and its facilities, along with a list of SAO research staff can be found at Smithsonian Opportunities for Research and Study.

Useful information for visitors is available at SAO Fellowship Program Resources.