Science fiction has popularized asteroid mining and cities in the sky, but could the future of mining be in cloud cities hanging far above distant worlds?

The asteroid mining industry would be incredibly profitable ... public and private investment in what was once considered science fiction. Last October, Nasa launched a mission to an M-type ...

Eric Mack is a reporter covering science, sustainability and space ... on the moon or elsewhere in space. Excitement for asteroid mining has dropped off a bit since it was attracting more ...