Meanwhile, platinum group elements, or PGEs, have the potential to provide untold wealth for us humans stuck back on Earth. They are already valuable in Earth markets, and if we can return them from space in massive quantities, there may be significant profits to be made. The problem is that, right now, we don’t exactly know exactly how much hydrogen or PGE you’d even collect if you were to grab a rock from a random asteroid’s surface: We need to do a bit of prospecting first. A wealth of data tells us hydrogen is in the moon, in larger abundances in permanently shadowed craters and, in albeit smaller quantities, bound up within the lunar soil itself. PGEs may be tougher to find, but commercial space should open up new and greater opportunities to keep looking for them.
The Proper Role of NASA – Slate Magazine