NASA Science News | 2015 May 11
[c]One day, when humans go to Mars, they might find that, occasionally, the Red Planet has green skies.
A map of MAVEN's Imaging Ultraviolet Spectrograph (IUVS) auroral detections in
December 2014 overlaid on Mars’ surface. The map shows that the aurora was
widespread in the northern hemisphere, not tied to any geographic location.
The aurora was detected in all observations during a 5-day period.
(Credits: University of Colorado)[/c]
In late Dec. 2014, NASA's MAVEN spacecraft detected evidence of widespread auroras in Mars's northern hemisphere. The "Christmas Lights," as researchers called them, circled the globe and descended so close to the Martian equator that, if the lights had occurred on Earth, they would have been over places like Florida and Texas.
"It really is amazing," says Nick Schneider who leads MAVEN's Imaging Ultraviolet Spectrograph (IUVS) instrument team at the University of Colorado. "Auroras on Mars appear to be more wide ranging than we ever imagined."
This isn't the first time a spacecraft has detected auroras on Mars. Ten years ago, the European Space Agency's Mars Express found an ultraviolet glow coming from "magnetic umbrellas" in the southern hemisphere. ...
"The canopies of the patchwork umbrellas are where we expect to find Martian auroras," says Schneider. "But MAVEN is seeing them outside these umbrellas, so this is something new." ...
"The particles seem to precipitate into the atmosphere anywhere they want," says Schneider. "Magnetic fields in the solar wind drape across Mars, even into the atmosphere, and the charged particles just follow those field lines down into the atmosphere." ...
MAVEN Detects Aurora and Mysterious Dust Cloud around Mars
NASA | GSFC | University of Colorado | MAVEN | 2015 Mar 18
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