An artist’s rendering shows MAVEN’s Imaging UltraViolet Spectrograph (IUVS) taking in the “Christmas Lights Aurora" on Mars. Photo by University of Colorado/NASA
HOUSTON, March 18 (UPI) -- Earth isn't the only planet that features the occasional light show high in its upper atmosphere. According to data captured by the NASA probe MAVEN, Mars featured a five-day-long aurora late last year.
Dubbed "Christmas lights," the onslaught of electromagnetic activity lit up the Martian atmosphere for nearly a week in the run up to December 25. The aurora was detected by MAVEN's Imaging Ultraviolet Spectrograph (IUVS). The light show spread across Mars' northern hemisphere -- much as the Northern Lights do on Earth.
An aurora is a phenomenon whereby a mass of highly charged particles (mostly electrons and protons) collides with the atmosphere, causing the gas particles to glow. The ionization and excitation of different gases causes varied coloration.
"What's especially surprising about the aurora we saw is how deep in the atmosphere it occurs - much deeper than at Earth or elsewhere on Mars," Arnaud Stiepen, IUVS scientist from University of Colorado, said in a press release. "The electrons producing it must be really energetic."
MAVEN was launched more than a year ago to help scientists better understand Mars' atmosphere -- and more specifically, why there is so little of it left.
"The MAVEN science instruments all are performing nominally, and the data coming out of the mission are excellent," said Bruce Jakosky, the mission's principle investigator and a scientist at Colorado's Laboratory for Atmospherics and Space Physics.
Researchers shared MAVEN's latest findings at this week's Lunar and Planetary Science Conference in Texas.
In addition to spotting the aurora, MAVEN also recently detected a mysterious dust cloud floating in Mars' thinning atmosphere, present between 93 miles and 190 miles from the Martian surface.
"This one was unexpected," Jakosky told conference attendees.
Researchers can't confirm where the dust originated. It could have wafted up from the lower atmosphere, scientists said. It also could come from one or both of Mars' two moons, Phobos and Deimos. Or it could have been delivered by passing comets or solar winds.
"If the dust originates from the atmosphere, this suggests we are missing some fundamental process," mission scientist Laila Andersson said.
