English: This artist's rendering represents a concept of possible activities during future space exploration missions. It depicts a crewmember planting an American flag on the surface of Mars.
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]