- Mars’ atmosphere is thin, and compared to Earth, it hardly exists at all, but it can still inform us about the history and current state of the planet.
- The ExoMars Trace Gas Orbiter probe, a project from the European Space Agency and Russia’s Roscosmos company, recently discovered gas it had never before found.
- Hydrogen chloride, which requires specific conditions for formation, has been discovered in the atmosphere, which raises many questions.
The Mars we see today is mostly dry, dusty, and arid. Sure, there is some water trapped in the ice near the poles, and maybe some melting that occurs during the year of Mars, but aside from that, there is very little that provides clues to the planet’s potentially rich and vibrant history. Projects like the ExoMars Trace Gas Orbiter, dispatched by the European Space Agency and the Russian space group Roscosmos, help pull the curtain and reveal some of the secrets the planet still holds.
Now, in a pair of new studies published in Science Advances, researchers using data from the Trace Gas Orbiter reveal that they have discovered a gas they had never seen before around Mars. Newly discovered gas, Hydrogen chlorideThe first halogen gas present in the Martian atmosphere appears to be linked to seasonal variations, but the discovery ultimately raises more questions than it answers.
A planet’s atmosphere may not seem like a critical thing to study, especially in the case of a thin atmosphere like Mars. But even though Mars’ atmosphere may not be sufficient to support life on its surface, it can still act as an indicator of the processes taking place on the planet’s surface. The exciting part about the discovery of hydrogen chloride in the Martian atmosphere is that it indicates that water was (or is) an important component of planet’s climate science.
“You need water vapor to release the chlorine and you need the by-products of water – hydrogen – to form hydrogen chloride. Water is crucial to this chemistry,” Kevin Olsen, co-author of the research, He said in a statement. “We also see an association with dust: We see more hydrogen chloride when dust activity escalates, a process associated with the seasonal heating of the Southern Hemisphere.”
But what does this mean exactly? Still hard to say. Whatever generates the gas, it appears associated with summer in the planet’s southern hemisphere, but beyond that, the chain of events that lead to its creation is difficult to pin down.
In the second paperThe researchers revealed that measurements of the ratio of deuterium to hydrogen in the planet’s atmosphere indicate massive water losses throughout the planet’s history. This supports the idea that Mars was rich in water and may have supported huge lakes, rivers and oceans on its surface.