Asteroid mining plans are not to bring resources back to Earth.

What all these articles are failing to realize is that at todays launch costs _anything_ already in orbit is worth several times it's weight in gold, minimum. Get 60 tons of water from an asteroid, it's worth a cool million dollars. Get 60 tons of any resource from an asteroid, it's worth a cool million dollars.

Nobody is going to bring anything back to earth, that would be ridiculous. You'd be better off filtering elements out of salt water.

Mining asteroids is so we can colonize the solar system cheaper.

The only thing that could compete with mining asteroids economically is a space elevator, which would have to be made out of unobtanium and which would attract terror attacks like moths to a flame.

http://www.bbc.co.uk/news/science-environment-17835607#

Mining asteroids for gold and platinum

24 April 2012 Last updated at 19:58 ET

 

Details have been emerging of a plan by billionaire entrepreneurs to mine asteroids for their resources.

The multi-million-dollar plan would use robotic spacecraft to squeeze minerals such as platinum and gold out of the rocks.