The images returned by NASA's MAVEN spacecraft offer greater insights into Mars on aspects like nightglow, cloud formation and volcanic activity at the red planet.
The photos show vivid details of many activities that were previously unknown. Offering valid clues on high-altitude winds and ozone variations, the pictures have been hailed as impeccable in terms of providing clues on the planet's ultraviolet radiations and surface, including the planet's south polar cap.
Captured by the Imaging UltraViolet Spectrograph, the images show how ozone volumes in Mars change with each season and how clouds form over volcanoes in the afternoon.
Launched in November 2013, the Mars Atmosphere and Volatile Evolution Mission or MAVEN has the mandate to explore the mysteries of the atmosphere and ionosphere of Mars, besides probing the planet's interactions with the sun.
Martian "Nightglow" Explained
NASA was also able to obtain details on the Martian nightglow, a planetary activity where the Martian sky keeps glowing dimly even without any external light. This glow has been attributed to the ultraviolet emission from nitric oxide. The sun's UV light breaks down the planet's carbon dioxide and nitrogen molecules on the side that faces the sun, resulting in atoms that get moved around by surrounding high-altitude winds.
When the atoms reach the nightside of Mars, these are brought down by the winds to a lower altitude and have a chemical reaction with oxygen. When the oxygen and nitrogen atoms collide, they form nitric oxide and release energy in the form of ultraviolet light, which explains the nightglow.
Ozone Volumes And Relation With Water Vapor
In the case of ozone and water vapor, there is a vanishing act by the former as it is eliminated when the latter is present. According to NASA, this means that ozone accumulates where there is no water vapor, or where the water vapor has been frozen out: the winter polar region.
Based on the photos sent back by MAVEN, ozone is present even in spring, suggesting that global winds prevent water vapor from reaching the winter polar regions. By studying the wave patterns on the images, scientists will be able to have a better understanding of the red planet's wind patterns and atmosphere circulation.
The images also explain the dynamics of cloud formation throughout the day, how the planet balances its energy and how much water vapor it has.
"MAVEN obtained hundreds of images in recent months, giving some of the best high-resolution ultraviolet coverage of Mars ever obtained," said Nick Schneider of the Laboratory for Atmospheric Physics at the University of Colorado. He will be presenting these findings at the American Astronomical Society Division for Planetary Sciences in Pasadena, California on Oct. 19.
Commenting on the MAVEN images, Justin Deighan of the University of Colorado, Boulder spoke how MAVEN was able to capture Mars' atmosphere in great detail.
"MAVEN's elliptical orbit is just right," said Deighan, who led the observations. "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 project is managed by NASA's Goddard Space Flight Center.