Vast areas of the Martian night sky pulse in ultraviolet light, according to images from NASA’s MAVEN spacecraft.
Vast areas of the Martian night sky pulse in ultraviolet light, according to images from NASA’s MAVEN spacecraft. The results are being used to illuminate complex circulation patterns in the Martian atmosphere.
The MAVEN team was surprised to find that the atmosphere pulsed exactly three times per night, and only during Mars’ spring and fall. The new data also revealed unexpected waves and spirals over the winter poles, while also confirming the Mars Express spacecraft results that this nightglow was brightest over the winter polar regions.
“MAVEN’s images offer our first global insights into atmospheric motions in Mars’ middle atmosphere, a critical region where air currents carry gases between the lowest and highest layers,” said Nick Schneider of the University of Colorado's Laboratory for Atmospheric and Space Physics (LASP), Boulder, Colorado. The brightenings occur where vertical winds carry gases down to regions of higher density, speeding up the chemical reactions that create nitric oxide and power the ultraviolet glow. Schneider is instrument lead for the MAVEN Imaging Ultraviolet Spectrograph (IUVS) instrument that made these observations, and lead author of a paper on this research appearing August 6 in the Journal of Geophysical Research, Space Physics. Ultraviolet light is invisible to the human eye but detectable by specialized instruments.
Read more at NASA / Goddard Space Flight Center
Image: This is an image of the ultraviolet “nightglow” in the Martian atmosphere. Green and white false colors represent the intensity of ultraviolet light, with white being the brightest. The nightglow was measured at about 70 kilometers (approximately 40 miles) altitude by the Imaging UltraViolet Spectrograph instrument on NASA’s MAVEN spacecraft. A simulated view of the Mars globe is added digitally for context. The image shows an intense brightening in Mars’ nightside atmosphere. The brightenings occur regularly after sunset on Martian evenings during fall and winter seasons, and fade by midnight. The brightening is caused by increased downwards winds which enhance the chemical reaction creating nitric oxide which causes the glow. Credits: NASA/MAVEN/Goddard Space Flight Center/CU/LASP
