The Mars Atmosphere and Volatile Evolution (MAVEN) mission has sent some new images from the planet showing an unprecedented level of detail of the “nightglow” that comes from the planet’s atmosphere. Images of the the ultraviolet glow, taken by the Imaging UltraViolet Spectrograph (IUVS), can tell scientists more about the day-to-day of the Red Planet.

"MAVEN obtained hundreds of such images in recent months, giving some of the best high-resolution ultraviolet coverage of Mars ever obtained," said Nick Schneider, instrument lead of the IUVS based at the Laboratory for Atmospheric and Space Physics at the University of Colorado, who is presenting the results Oct. 19 at the American Astronomical Society Division for Planetary Sciences meeting in Pasadena, Calif.

The spacecraft, which arrived at Mars on Sept. 21, 2014, has images from the nightside and the dayside of the planet. Imagery from the former can tell scientists how winds on Mars circulate at such high altitudes. Images from the latter can show how ozone amounts differ from season-to-season and how clouds are formed over volcanoes on the planet.

iuvs_1_clean_with_insetjpg This image of the Mars night side shows ultraviolet emission from nitric oxide (abbreviated NO). The emission is shown in false color with black as low values, green as medium, and white as high. These emissions track the recombination of atomic nitrogen and oxygen produced on the dayside, and reveal the circulation patterns of the atmosphere. The splotches, streaks and other irregularities in the image are indications that atmospheric patterns are extremely variable on Mars' nightside. The inset shows the viewing geometry on the planet. MAVEN's Imaging UltraViolet Spectrograph obtained this image of Mars on May 4, 2016 during late winter in Mars Southern Hemisphere. Photo: NASA/MAVEN/University of Colorado

On Mars, ultraviolet light from the sun breaks down carbon dioxide and nitrogen molecules. High-altitude winds carry the broken down molecules around the planet. When they arrive to the nightside, the molecules go to a lower altitude and combine with nitrogen and oxygen atoms to create nitric oxide molecules. The formation of nitric oxide molecules releases extra energy, which manifests as ultraviolet light causing the sky to glow.

In the past, scientists anticipated Mars to have nightglow and previous missions had detected the presence of ultraviolet light. But the new images are the first to capture this effect in the atmosphere of Mars. According to NASA, “splotches and streaks” on the image indicate where nitric oxide is forming.

“Such concentrations are clear evidence of strong irregularities in Mars' high altitude winds and circulation patterns,” says NASA in a statement. “These winds control how Mars' atmosphere responds to its very strong seasonal cycles.”

Mars-MAVEN-New-Images-Ozone-Poles This ultraviolet image near Mars’ South Pole was taken by MAVEN on July 10 2016 and shows the atmosphere and surface during southern spring. The ultraviolet colors of the planet have been rendered in false color, to show what we would see with ultraviolet-sensitive eyes. Darker regions show the planet's rocky surface and brighter regions are due to clouds, dust and haze. The white region centered on the pole is frozen carbon dioxide (dry ice) on the surface. Pockets of ice are left inside craters as the polar cap recedes in the spring, giving its edge a rough appearance. High concentrations of atmospheric ozone appear magenta in color, and the wavy edge of the enhanced ozone region highlights wind patterns around the pole. Photo: NASA/MAVEN/University of Colorado

Images from the dayside show the atmosphere and surface around Mars’ south pole as the season transitions into spring. Ozone amounts change with the seasons on the planet, as its presence relies on water vapor, which destroys ozone. In the winter, when water vapor is frozen out of the atmosphere, ozone accumulates. But as water vapor becomes present in the atmosphere, ozone levels drop. The new images show ozone in spring, suggesting that “global winds are inhibiting the spread of water vapor from the rest of the planet into winter polar regions.”

“Wave patterns in the images, revealed by UV absorption from ozone concentrations, are critical to understanding the wind patterns, giving scientists an additional means to study the chemistry and global circulation of the atmosphere,” writes NASA.

NASA-MAVEN-Mission-Cloud-Formation-Images-Volcanoes MAVEN's Imaging UltraViolet Spectrograph obtained these images of rapid cloud formation on Mars on July 9-10, 2016. The ultraviolet colors of the planet have been rendered in false color, to show what we would see with ultraviolet-sensitive eyes. The series interleaves MAVEN images to show about 7 hours of Mars rotation during this period, just over a quarter of Mars' day. The left part of the planet is in morning and the right side is in afternoon. Mars’ prominent volcanoes, topped with white clouds, can be seen moving across the disk. Mars’ tallest volcano, Olympus Mons, appears as a prominent dark region near the top of the images, with a small white cloud at the summit that grows during the day. Olympus Mons appears dark because the volcano rises up above much of the hazy atmosphere which makes the rest of the planet appear lighter. Three more volcanoes appear in a diagonal row, with their cloud cover merging to span up to a thousand miles by the end of the day. These images are particularly interesting because they show how rapidly and extensively the clouds topping the volcanoes form in the afternoon. Similar processes occur at Earth, with the flow of winds over mountains creating clouds. Afternoon cloud formation is a common occurrence in the American West, especially during the summer. Photo: NASA/MAVEN/University of Colorado

MAVEN also captured images of afternoon cloud formation over four volcanoes on Mars. These images show how clouds develop over the giant volcanoes throughout the day. According to NASA, clouds are important for understanding the “planet’s energy balance and water vapor inventory” and will shed insight into the daily and seasonal behavior of the atmosphere of the planet.

"MAVEN's elliptical orbit is just right," said Justin Deighan of the University of Colorado, Boulder, who led the observations, in a statement. "It rises high enough to take a global picture, but still orbits fast enough to get multiple views as Mars rotates over the course of a day."

The MAVEN mission is part of NASA’s Mars Scout program and is managed by the Goddard Space Flight Center. The spacecraft launched in Nov. 2013 to gather data on the planet’s atmosphere, ionosphere and interactions with solar wind and the sun. In addition to the IUVS, the MAVEN has seven other instruments: a Neutral Gas and Ion Mass Spectrometer, a Langmuir Probe and Waves, a Solar Wind Electron Analyzer, a Solar Wind Ion Analyzer, a Solar Energetic Particles, and a SupraThermal And Thermal Ion Composition.