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Summary

DescriptionGlobal Lightning Frequency.png	English: Data from space-based sensors reveal the uneven distribution of worldwide lightning strikes. Units: flashes/km²/yr. Data obtained from April 1995 to February 2003 from NASA's Optical Transient Detector and from January 1998 to February 2003 from NASA's Lightning Imaging Sensor.
Date	10 December 2001
Source	http://www.nasa.gov/centers/goddard/news/topstory/2004/0621lightning_prt.htm http://visibleearth.nasa.gov/view_rec.php?id=2264
Author	NASA/GHRC/NSSTC Lightning Team
Other versions	File:Global lightning strikes.png

Licensing

	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."

Old file history

Originally uploaded to Dansk Wikipedia on by Glenn.

Information

File history

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	Date/Time	Dimensions	User	Comment
current	05:31, 26 May 2013	1,860 × 880 (133 KB)	Yourmomblah	Optimized file size
	04:42, 29 December 2009	1,860 × 880 (335 KB)	Rehman	Higher quality
	15:47, 6 November 2005	1,205 × 586 (326 KB)	Tintazul	Higher resolution, same source
	08:50, 2 July 2005	540 × 307 (42 KB)	Saperaud~commonswiki	original uploaded 7. Nov 2003 in Dansk wikipedia by da:Bruger:Glenn Fra hollandsk Wikipedia (Bliksem). Kilde NASA: http://visibleearth.nasa.gov/cgi-bin/viewrecord?10812 . http://visibleearth.nasa.gov/help.html Citat: "...Unless otherwise noted, all