“Chilling Discovery: Frost on Mars’ Volcanoes Holds Water for 60 Olympic Pools!”

We inhabitants of Earth are all too acquainted with frost. That crisp, white coating we observe on chilly mornings, which develops when atmospheric moisture condenses and freezes on surfaces, is a hallmark of terrestrial winters.However, on Mars, where the atmosphere is approximately 100 times less dense and contains 10,000 times fewer water vapours than Earth, such icy occurrences are highly improbable.

Against all expectations, researchers have identified water frost at the equator of Mars for the very first time! Even more remarkable, this finding took place in a Martian area once deemed impossible for frost to exist.
Space cameras examine Martian summits, revealing their frosty mysteries
The frosty discoveries stem from observations of the Tharsis region on Mars, which encompasses some of the tallest volcanoes in the solar system: Olympus Mons, Arsia Mons, Ascraeus Mons, and Ceraunius Tholus. Here, traces of temporary morning frost were found on the volcanoes’ summits, locations previously believed to be too warm for frost formation.

This breakthrough was initiated with the observation of lighter, bluish regions on the summits of the volcanoes by the Colour and Stereo Surface Imaging System (CaSSIS) aboard ESA’s ExoMars Trace Gas Orbiter (TGO). Initially perplexing, these bright patches were consistently visible only during early morning examinations in Mars’ cold seasons.

Further examination verified that these lighter regions were indeed water frost, as the High-Resolution Stereo Camera (HRSC) on ESA’s Mars Express also documented these features. However, the cause of this phenomenon remained elusive until investigators performed numerical simulations to recreate the Martian volcanoes’ microclimate.

These simulations, akin to those applied in forecasting Earth’s weather but adapted for Martian conditions, demonstrated that the clear zones aligned with circumstances favorable for water condensation. They established that these icy spots resulted from frost forming overnight under suitable climatic conditions on Mars.

The simulations also indicated that surface temperatures on these Martian volcanoes are appropriate for frozen water to exist. Nevertheless, the intense solar exposure at the equator leads to a rapid dissipation of frost each morning, thus elucidating its ephemeral nature.

The frost layer is exceptionally thin, merely 10 micrometres in thickness, reflecting Mars’ scarce atmospheric water vapour. In terms of volume, the frost could potentially cover around 60 Olympic-sized swimming pools if collected. While this may appear significant, it is a trivial amount compared to Mars’ overall surface area. Regardless, it signifies a potential resource for upcoming astronauts, who might utilize it for drinking water or converting it to rocket fuel.

This finding not only enriches our comprehension of Mars’ current water cycle but also provides insights into its historical climate and possible habitability. By enhancing our understanding of Martian meteorological patterns, we can better equip ourselves for future explorations and continue to decode the enigmas of the Red Planet.

These results were recently published in the journal Nature Geoscience and can be accessed here.