He said multibillion-dollar companies and entrepreneurs were increasingly looking into our solar system for the "infinite resources" readily available there.
"Not only solar power but in the asteroid belt - there's everything you might need."
That included metal materials, he said.
"The famous quote is that there's enough to build a skyscraper 8000 storeys tall and cover the Earth in it - which no one wants to do - but we're just saying there's a lot there.''
Re-usable rockets sourced by multibillion-dollar companies meant there was now access to orbit never seen before.
That therefore made the dream to do such things in outer space a more viable plan.
"Now we have the means to get there...we have the technology to go.
"It's almost a golden scenario that becomes available - where you can expand and grow our civilisation and increase living standards for everybody without using the resources of the planet. And that's the key point.
Asked whether he thought his grandchildren's generation might see us mining the asteroid belt, his response was immediate.
"I think before that."
He had visited asteroid companies who were already putting legal frameworks together, he said.
"So we're at the position now where we have the spacecraft, we have the launches and we have the will, so I think the commercial imperative will drive it."