Tuesday, January 17, 2017

Asteroid Mining

1/17/17 U.K. Daily Star is a very tabloidish paper, so perhaps less meaningful than it appears:
NASA to explore space rock worth so much money it would DESTROY world economy

The 200km-wide asteroid, named Psyche, is currently orbiting the sun between Mars and Jupiter.
It is made up of various precious metals such as iron, nickel and gold.
Experts believe the iron alone in the rock would be worth $10,000 quadrillion – enough to cause the world’s economy, worth $73.7 trillion, to promptly collapse altogether.
I can see how it might destroy iron, nickel, cobalt, gold, and platinum mining--if you could figure out how to extract it.  (But cheap metals would provoke an economic boom) But how do you land the pieces?  ISIS, we have a gift for you, every week, for the next century, or until you come to your senses.  It is believed that Sudbury, Ontario's nickel is extraterrestrial in origin:
The Sudbury Basin, which is the world's second-largest impact crater, was likely formed by an enormous comet that battered Earth more than 1.8 billion years ago, new research suggests....
Ever since miners discovered rich deposits of copper, nickel, palladium and other valuable metals there in the 1880s, scientists have wondered how the giant hole in the Earth came into existence, said study co-author Joseph Petrus, an earth sciences doctoral candidate at Laurentian University in Sudbury.
As I mentioned a few weeks ago, nickel-iron is very tough, tougher than stainless steel.  Also, how do you cut something that  can turn or move away from any force?  Reaction thrusters can start it turning, and perhaps the inertia of it would allow cutting, but if it has that much inertia, it will be a lot of energy to get it spinning, I think.

3 comments:

Billy Oblivion said...

Read the "Troy Rising" series by John Ringo.

The short answer is mirrors.

Lots of mirrors.

Clayton Cramer said...

Mirrors melt it. But once it freezes, how do you slice off chunks? You can burn into the metal, I think, but Ni-FE conducts heat so well that I doubt it would work to remove small pieces.

Karl said...

I read an SF story where the metal mined from an asteroid was melted and formed into a hollow sphere. A large enough sphere, formed in a vacuum, would have a very low average density.

At sea level, air has a density of about 1 kg per cubic meter. Iron has a density of 8 metric tons per cubic meter. So if you could form iron into a structure that is at least 99.99% empty space, it would float above the surface until enough air leaked in to increase the weight above the weight of the air displaced. The author ran numbers and came up with a sphere large enough that the shell could be thick enough to resist air pressure for quite a while.

In the story, he arranged for the sphere to come to rest over Washington DC, and challenged Congress to dispense with regulations blocking the delivery of asteroid mined metals to Earth before the sphere settled the rest of the way to the ground.