Is it possible to find underground metal deposits from orbit using satellites (or spacecraft with suitable sensors)?

What are you thinking about as the practical limits on a suitable sensor? Also, do you mean sheets of electrically conductive metal, or the more common metal-oxides and metal-silicates in our rocks? I think you could probably detect mineral content with a suitable large MRI device, but building it and getting it into orbit might take quintillions of dollars.

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Forming opinions as we speak

Search engines are your friend:

Satellite mineral survey search

I take it from some of the stuff on that link that it IS possible. Ok, next question: Why haven't we done this with the moon or mars?

Mars Reconnaissance Orbiter CRISM

For instance: The Minerals of Candor Chasma



CRISM :: Science

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