Ponzo_illusion.gif

Licensing

Description

English: Ponzo illusion

Date

before 20 June 2005

Source

Author

Permission
( Reusing this file )

	This file is in the public domain in the United States because it was solely created by NASA . NASA copyright policy states that "NASA material is not protected by copyright unless noted ". (See Template:PD-USGov , NASA copyright policy page or JPL Image Use Policy .)
	Warnings: Use of NASA logos , insignia and emblems is restricted per U.S. law 14 CFR 1221 . 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. Materials based on Hubble Space Telescope data may be copyrighted if they are not explicitly produced by the STScI . [1] See also {{PD-Hubble}} and {{Cc-Hubble}} . 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] Images featured on the Astronomy Picture of the Day (APOD) web site may be copyrighted. [3] The National Space Science Data Center (NSSDC) site has been known to host copyrighted content . Its photo gallery FAQ states that all of the images in the photo gallery are in the public domain "Unless otherwise noted."