Presented at the National Astronomy Meeting of the Royal Astronomical Society, a study points towards a new link between solar storms and Martian weather.
Researchers have discovered evidence of warming in the Red Planet’s lower atmosphere when two major eventsa solar energetic particle (SEP) storm and a global dust storm, occurred simultaneously in June 2018.
How was this interaction discovered?
A team from Lancaster University looked at five SEP events to assess their impact on Mars. Four of them showed no clear effect.
However, the fifth coincided with the dust storm that ended the mission of NASA’s Opportunity rover. It was during this combined event that scientists detected signs of atmospheric warming.
The astronomers used data from NASA’s MAVEN probe and ESA’s TGO orbiter. By comparing observed temperatures with expected climate models, they found that the warming pattern could not be explained by the dust storm alone.
Why is Mars so vulnerable to this phenomenon?
Unlike Earth, Mars is particularly exposed to solar particles. The Red Planet has a very thin atmosphere and lacks a strong global magnetic field to protect it.
Energetic particles from solar flares can therefore penetrate deep into its atmosphere. If previous research had already shown the impact of these particles on the upper atmosphere, their effect on lower layers remained poorly understood.
Dust storms, on the other hand, are known to heat the Martian atmosphere by absorbing light from the Sun. However, the warming observed during the 2018 event was unusual and did not fit classic models of a dust storm alone.
Atmospheric models of Mars to be improved?
Although the researchers insist on the preliminary nature of the discovery, it opens up perspectives.
The idea that Martian weather could result from a combination of internal and external factors complicates the vision of the planet. Mars’ atmosphere and weather may respond to several events acting together.
Further observations will be necessary to confirm whether such an interaction is systematic.
