English: John Houbolt explaining his Lunar Orbital Rendezvous plan for landing on and returning from the moon, to be used in the then-nascent Apollo program.
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.
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