In his book, “Mining The Sky: Untold Riches of the Asteroids, Comets and Planets,”author John S. Lewis takes an in-depth look at the prospects for accessing resources in space. In one of his most dramatic estimates, he highlights the asteroid 3554 Amun, a metallic asteroid, as potentially having $20 trillion in gold beneath its surface, along with another $8 trillion in iron and nickel, $6 trillion in cobalt and $6 trillion in platinum.
The book, which was published in 1997, included estimates based on market prices at the time, which were close to one-sixth of 2011 prices. Any student of supply and demand would assume that if such an influx of precious metals were brought to the planet in abundance, prices for these metals would tank.
But is Lewis far off? Although his estimates likely can’t be verified without surface probes and sophisticated measurements, it may not be too far of a stretch. A new study this yearfound that gold on Earth’s surface was primarily brought to the planet by asteroids. The rationale is that when the molten earth was forming, the heavy metals, such as gold, sunk to the core and only after the surface cooled did metals remain near the surface. After the planet cooled, the only source of gold and other heavy metals was from outer space, most commonly from asteroids.