We are now finding out just how little we knew about Mars. NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft arrived in Mars orbit in September, and is studying the upper atmosphere of the planet.
There have been two unexpected phenomena discovered in the atmosphere of Mars.
High altitude dust cloud
There was a presence of a high altitude dust cloud. This presence of dust orbiting at high altitudes—about 93 miles, or 150 kilometers, to 190 miles, or 300 kilometers above the surface—was not predicted.
“If the dust originates from the atmosphere, this suggests we are missing some fundamental process in the Martian atmosphere,” said Laila Andersson of the University of Colorado’s Laboratory for Atmospherics and Space Physics (CU LASP), NASA said on their webpage.
MAVEN spots unexplained dust in the Martian atmosphere:
The Langmuir Probe and Waves (LPW) instrument on MAVEN detected the cloud. It is not known if the cloud is temporary or whether it is a longer lasting event. But it has been there since the spacecraft has been in operation. No other instruments on MAVEN have indicated the presence of this cloud.
Possible sources for the observed dust include dust wafted up from the atmosphere; dust coming from Phobos and Deimos, the two moons of Mars; dust moving in the solar wind away from the sun; or debris orbiting the sun from comets. However, no known process on Mars can explain the appearance of dust in the observed locations from any of these sources, reported NASA.
Ultraviolet auroral glow
The Imaging Ultraviolet Spectrograph (IUVS), an instrument on Maven, saw an ultraviolet auroral glow spanning Mars’s northern hemisphere. For five days just before Dec. 25, scientists observed what they named “Christmas lights.”
On NASA’s website it said: “What’s 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.”
Stiepen went on to say that the source of the energetic particles appears to be the sun. MAVEN’s Solar Energetic Particle instrument detected a huge surge in energetic electrons at the onset of the aurora. Billions of years ago, Mars lost a global protective magnetic field like Earth has, so solar particles can directly strike the atmosphere. The electrons producing the aurora have about 100 times more energy than you get from a spark of house current, so they can penetrate deeply in the atmosphere.
NASA’s MAVEN spacecraft explores the possibility of man going to Mars:
It will be interesting to find out more about this planet in the near future, as it is proving to be a treasure trove of new discoveries.