According to John Updike, Mars has long exerted a pull on the human imagination. The erratically moving red star in the sky was seen as sinister or violent by the ancients: The Greeks identified it with Ares, the god of war; the Babylonians named it after Nergal, god of the underworld. To the ancient Chinese, it was Ying-huo, the fire planet.
Mars has attracted so much attention as no other planet would. Every Nation dreams to reach Mars in due time.
Therefore several missions including Pathfinder, Mars series, Curiosity, Vikings etc has been sent to Mars. We dream so much about Mars, yet our knowledge about it remains vague.
ExoMars(Exobiology on Mars) is Mars reconnaissance and astrobiology programme being undertaken by the European Space Agency (ESA) and the Russian space agency Roscosmos.
The aim remains:
- To search for remnant signs of past life on Mars or its biosignatures.
- Investigate any difference between the Martian water and geochemical environment from the ones we have.
- Investigate atmospheric trace gases and their sources.
- Choose the technologies for a future Mars sample-return mission, removing any possible hazards to our future missions.
All this is done while feeding on Solar electric power on Martian foreign land.
But it is the absolute first time that a new gas and new revelations of how the Martian water disappeared are found in the pages of cosmic history. Finding of Hydrogen chloride marks the discovery of halogen gas in the atmosphere of Mars and consequently triggers a new chemical cycle to understand further.
Mars scientists were anyways looking for chlorine- or sulphur-based gases because they are possible indicators of volcanic activity but detection of only aforesaid gas and no other suggests an entirely new surface-atmosphere interaction driven by the dust seasons on Mars that previously remained unexplored.
Sunlight warms the atmosphere causing dust to rise. The salty dust reacts with atmospheric water to release chlorine, reaction with available hydrogen yields hydrogen chloride.
Further reactions could see the chlorine or hydrochloric acid-rich dust return to the surface, perhaps as perchlorates, a class of salt made of oxygen and chlorine.
The sensitive instruments also observed a correlation to dust: more hydrogen chloride is seen when dust activity ramps up, a process linked to the seasonal heating of the southern hemisphere of Mars.
The two new results from the ExoMars team published today in Science Advances unveil an entirely new class of chemistry and provide further insights into seasonal changes and surface-atmosphere interactions as driving forces behind the new observations.
“The discovery of the first new trace gas in the atmosphere of Mars is a major milestone for the Trace Gas Orbiter mission,” says Håkan Svedhem, ESA’s ExoMars Trace Gas Orbiter project scientist.
In 2015, the pictures of leaked water on Mars were quite evident. It revealed the ancient dried out valleys and river channels. Today, it lies locked up in the ice caps and buried underground.
For more details: https://www.nasa.gov/press-release/nasa-confirms-evidence-that-liquid-water-flows-on-today-s-mars
The tepid presence of water vapour and semi-heavy water (one hydrogen atom is replaced by a deuterium atom)is key to understanding of such changes. The deuterium to hydrogen ratio or D/H is a parameter to gauge the history of water on Mars, and how water loss happened over time.
The evolution of the climate on Mars can be well understood by such integration of trapped Martian water and its seasonal behaviour.
ExoMars data collected between April 2018 and April 2019 also showed three instances that accelerated water loss from the atmosphere to be linked to seasonal changes:
- The global dust storm of 2018
- A regional storm in January 2019
- Water release from the south polar ice cap during summer months
For when sustainability on Earth is in perils and new advancements are made with technology, Mars is not far away.