Title: Official portrait of STS-50 USML-1 backup Payload Specialist Joseph M. Prahl
Description: Joseph M. Prahl poses for his official portrait as STS-50 Columbia, Orbiter Vehicle (OV) 102, United States Microgravity Laboratory 1 (USML-1) backup (alternate) payload specialist. Prahl is from Case Western Reserve University.
The NASA website hosts a large number of images from the Soviet/Russian space agency, and other non-American space agencies. These are not necessarily in the public domain.
The SOHO (ESA & NASA) joint project implies that all materials created by its probe are copyrighted and require permission for commercial non-educational use. [2]