Image: Saturn's double aurorae (captured by the Hubble Space Telescope)

Description: Image of Saturn and its polar aurorae from vertically above its equator in light of 115 and 125 nanometres of wavelength (ultraviolet light) taken by the Hubble Space Telescope in 2009. In January and March 2009, astronomers using NASA's Hubble Space Telescope took advantage of a rare opportunity to record Saturn when its rings were edge-on, resulting in a unique movie featuring the nearly symmetrical light show at both of the giant planet's poles. It takes Saturn almost thirty years to orbit the Sun, with the opportunity to image both of its poles occurring only twice during that time. The light shows, called aurorae, are produced when electrically charged particles race along the planet's magnetic field and into the upper atmosphere where they excite atmospheric gases, causing them to glow. Saturn's aurorae resemble the same phenomena that take place at the Earth's poles.
Title: Saturn's double aurorae (captured by the Hubble Space Telescope)
Credit: http://hubblesite.org/newscenter/archive/releases/2010/09/image/a/ (direct link) http://www.spacetelescope.org/images/heic1003a/
Author: NASA, ESA, and Jonathan Nichols (University of Leicester)
Permission: This file is in the public domain because it was created by NASA and ESA. NASA Hubble material (and ESA Hubble material prior to 2009) is copyright-free and may be freely used as in the public domain without fee, on the condition that only NASA, STScI, and/or ESA is credited as the source of the material. This license does not apply if ESA material created after 2008 or source material from other organizations is in use. The material was created for NASA by Space Telescope Science Institute under Contract NAS5-26555, or for ESA by the Hubble European Space Agency Information Centre. Copyright statement at hubblesite.org or 2008 copyright statement at spacetelescope.org. For material created by the European Space Agency on the spacetelescope.org site since 2009, use the Template:ESA-Hubble tag.
Usage Terms: Public domain
License: Public domain
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