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]
Uploaded a work by NASA Earth Observatory from https://earthobservatory.nasa.gov/images/148655/an-upended-ecosystem-in-the-arabian-sea with UploadWizard