Trifid nebula from en-wiki. Copied from en-wiki, description from there follows: –Janne Karaste 07:22, 28 Feb 2005 (UTC)
DESCRIPTION: The Trifid nebula (M20, NGC NGC 6514) in pseudocolor.
Image taken with the Palomar 1.5-m telescope. The field of view is 16’ ´ 16’. Red shows [S II] ll 6717+6731. Green shows Ha l 6563. Blue shows [O III] l 5007. The WFPC2 field of view is indicated.
CREDIT: Jeff Hester (Arizona State University), Palomar telescope. SOURCE:http://hubblesite.org/newscenter/newsdesk/archive/releases/1999/42/image/e COPYRIGHT:“Unless otherwise specifically stated, no claim to copyright is being asserted by STScI and it may be freely used as in the public domain in accordance with NASA's contract. However, it is requested that in any subsequent use of this work NASA and STScI be given appropriate acknowledgement.”
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]