Just a day afterskywatchers at mid- to upper-latitudes around the world were treated to a particularly energetic display of auroras on the night of March 17 as a result of an intense geomagnetic storm,researchers announced findings from NASAsMAVENmission of auroral action observed on Mars although in energetic ultraviolet wavelengths rather than visible light.

Detected by MAVENsImaging Ultraviolet Spectrograph (IUVS) instrument overfive days beforeDec. 25, 2014, the ultraviolet auroras have been nicknamed Mars Christmas lights. They were observed across the planets mid-northern latitudes and are the result of Mars atmosphere interacting directly with the solar wind.

While auroras on Earth typically occur at altitudes of 80 to 300 kilometers (50 to 200 miles) and occasionally even higher, Mars atmospheric displays were found to bemuch lower, indicating higher levels of energy.

Whats especially surprising about the aurora we saw is how deep in the atmosphere it occurs much deeper than at Earth or elsewhere on Mars, said Arnaud Stiepen, IUVS team member at the University of Colorado. The electrons producing it must be really energetic.

To a human observer on Mars the light show probably wouldnt be very dramatic, though. Without abundant amounts ofoxygen and nitrogen in its thin atmosphere a Martianaurora would be a dimblue glow at best, if not out of the visible spectrum entirely.

This isnt the first time auroras have been spottedon Mars; observations with ESAs Mars Express in 2004 were actually thefirst detectionsof the phenomenon on the Red Planet. Made with the spacecrafts SPICAM ultraviolet spectrometer, the observations showed that Mars auroras are unlike thosefound anywhere else in the Solar System in that they are generated by particle interactions with very localized magnetic field emissions, rather than a globally-generated one (like Earths).

(So no, its not a total surprise but its still very cool!)

In addition to auroras MAVEN also detected diffuse but widespread dust clouds located surprisingly high in the Martian atmosphere. Its not yet understood what process is delivering dust so high 150-300 kilometers up (93-186 miles) or if itis a permanent or temporary feature.

Read more in the MAVEN news release here.

Source: NASA andNature

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NASA orbiter detects ultraviolet auroras on Mars