NASA's InSight mission finds a low amount of ice at the Martian equator

An analysis of seismic data from NASA's Mars InSight mission suggests that there is little or no ice on the Martian equator.NASA's Mars InSight mission has analyzed seismic data to show that the equator of Mars is devoid of ice.

Geophysical Research Letters describes the dry conditions beneath the landing site near the Martian equator, in the top 300 metres of the subsurface.

According to geophysicist Vashan Wright of Scripps Institution of Oceanography at UC San Diego, Mars' crust is weak and porous. The sediments are not well-cemented, and there is no ice filling the pore spaces.

According to Wright, these findings do not exclude the possibility that there may be grains or balls of ice that are not tying minerals together. 'Is ice likely to exist in that form?'

Additionally, the team discovered that the red planet may have held oceans of water in its early history. It has been suspected by many experts that much of the water became part of the underground cement minerals.

'Water creates new minerals when it comes into contact with rocks, like clay, so it's not a liquid. It's a part of the mineral structure,' said Michael Manga of the University of California Berkeley. 'There is some cement in the rocks, but they are not full of it.'

'Uncemented subsurfaces do not preserve records of biological activity or life, even though water may go into mineral deposits that don't act as cement.' Wright explains.

Rocks and sediments are protected from erosion by cement because the material holds them together by nature.

The lack of cemented sediment suggests a water shortage 300 metres below InSight's landing site near the equator. If there were water on Mars, conditions would be cold enough to freeze it due to the below-freezing average temperature at the equator.

The Martian subsurface is suspected to be full of ice by many planetary scientists, including Manga. It has melted away their suspicions. At the Martian poles, frozen ground ice and big ice sheets remain.

'Scientists have now been presented with the best data, the best observations. We predicted that frozen ground would still exist at that latitude with aquifers beneath,' said Manga, professor and chair of Earth and planetary science at UC Berkeley.

Elysium Planitia is a smooth, flat plain near the Martian equator where the InSight spacecraft landed in 2018. Among its instruments was a seismometer for measuring marsquakes and meteorite crashes.

The reason scientists want to probe the subsurface is that if there is life on Mars, it will probably be located there. Surface water is nonexistent, and subsurface life would not be exposed to radiation.

The Mars Life Explorer mission concept is NASA's next priority after a sample-return mission. In high latitudes, ice, rock, and the atmosphere will meet to drill two metres into the Martian crust in search of life.