From: Mars Society
Posted: Tuesday, July 31, 2001
At the end of Rotation 3, the Magnet Array (MA) was viewed (and photographed by Brent Bos): There were no magnetic dust patterns visible on the MA.
To confirm that such lack of patterns was not a consequence of the soil below the "Habitat" being slightly wet and therefore unable to be lifted by the wind and borne to the magnets, some dried soil from the area around the "Habitat" was blown onto the MA. Neither this dust stayed on the MA.
This indicates that there is no (or very little) magnetic minerals in the soil around the "Habitat".
This result is further verified by a low iron content in the soil (less than 2.5 mg per litre) found by Christine Jayarajah.
Let us pause to think of this result.
By looking at the landscape around the "Habitat", one is reminded of the Martian landscape. Therefore it is a great place for simulating exploration operations.
However, the geology of the soil on Devon is indeed different from that of the Martian soil. On Devon the soil is mostly dolomite, a calcium-magnesium carbonate ((Ca,Mg)CO3), with a low iron content and a low, if any, abundance of magnetic minerals. In contrast, on Mars, vast amounts of carbonate have not been found, but the soil contains a high percentage of iron and a strongly magnetic mineral.
The MA has been deployed at Mars-like places on Earth such as Hawaii and the deserts of Ghana. In these places, the Martian dust pattern has not been fully reproduced.
We are still intrigued by understanding how the Martian soil formed: Is it formed by water, dry breakdown, UV-radiation or perhaps biology?
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