MAVEN took the first image in July 2022
NASA's MAVEN (Mars Atmosphere and Volatile EvolutioN) spacecraft has released stunning ultraviolet images of Mars showing it in a whole new light. The spacecraft acquired these views of the planet at different points as it orbited around the sun.
The scientists were able to gain better insight into the red planet's atmosphere by viewing it in ultraviolet wavelengths. MAVEN was launched in November 2013 and it entered Mars' orbit in September 2014.
According to a news release by NASA, the MAVEN's Imaging Ultraviolet Spectrograph (IUVS) instrument obtained these global views of Mars in 2022 and 2023 when the planet was near opposite ends of its elliptical orbit.
The IUVS instrument measures wavelengths between 110 and 340 nanometers, outside the visible spectrum. To make these wavelengths visible to the human eye and easier to interpret, the images are rendered with the varying brightness levels of three ultraviolet wavelength ranges represented as red, green, and blue. In this colour scheme, atmospheric ozone appears purple, while clouds and hazes appear white or blue. The surface can appear tan or green, depending on how the images have been optimized to increase contrast and show detail, the release said.
MAVEN took the first image in July 2022 during the southern hemisphere's summer season, which occurs when Mars passes close to the Sun.
Elaborating about the season, NASA said that the summer season is caused by the tilt of the planet's rotational axis, similar to seasons on Earth.
The second image is of Mars' northern hemisphere and was taken in January 2023 after Mars had passed the farthest point in its orbit from the Sun.
Scientists hope that this will help them better understand the history of Mars's atmosphere, climate and liquid water.
Argyre Basin, one of Mars' deepest craters, appears at the bottom left filled with atmospheric haze (depicted here as pale pink). The deep canyons of Valles Marineris appear at the top left filled with clouds (coloured tan in this image). The southern polar ice cap is visible at the bottom in white, shrinking from the relative warmth of summer. Southern summer warming and dust storms drive water vapour to very high altitudes, explaining MAVEN's discovery of enhanced hydrogen loss from Mars at this time of year.
The deep canyons of Valles Marineris can be seen in tan at the lower left, along with many craters. Ozone, which appears magenta in this UV view, has built up during the northern winter's chilly polar nights. It is then destroyed in the northern spring by chemical reactions with water vapour, which is restricted to low altitudes of the atmosphere at this time of year.