Replies

I don't think iron oxide is magnetic.

It isn't. That's why I prefaced the idea by saying "any remaining iron in the iron oxide".

I also thought about the static electricity idea, but similar to you, I rejected it as being a probably cause, as I just can't see that force holding soil particles together in clumps very well.

Perhaps the "dust" has good insulating properties, and perhaps there could be some sort of liquid just under the surface. In direct sunlight, the martian surface DOES warm up close to and even above freezing, I believe, at certain times of the year.

So... just how big would a quick discovery of some liquid just under the surface be? It would be HUGE! Discovery of microbial life would be almost certain to quickly follow, and that... I can't even fathom the reaction. But I am almost expecting it, because I do believe Mars once harbored life to some degree, and may still, to this day...