"space mining's hard to imagine, but it's already been done and...

"space mining's hard to imagine, but it's already been done and samples dropped off back to Earth from distant asteroids, some planets and the moon."

Above is your quote for reference.

The compositional data from Mars you're found and are confusing yourself with has been obtained via light spectroscopy. Unless you are claiming physical samples were used for the analysis - please confirm if this is the case.

Also, your quote (above) states "some planets" can you back this statement up in any way?