English: Original Caption:
Viking 2 Orbiter image of Phobos orbiting over Ascraeus Mons on Mars. Phobos is about 8000 km below the spacecraft and 22 km across. Ascraeus Mons is 13,000 km away and about 300 km at its base, centered at 11 N, 104 W. North is at 11:30, and Phobos is moving from left to right relative to the surface.
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]