NASA Earth Observatory image by Robert Simmon, using Landsat data from the U.S. Geological Survey. Caption by Michon Scott and Mike Carlowicz, with information from Dan Slayback and Dorothy Hall, NASA Goddard Space Flight Center, and Lonnie Thompson, Byrd Polar Research Center.
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]