Elon Musk says

“If humanity is to become multi-planetary, the fundamental breakthrough that needs to occur in rocketry is a rapidly and completely reusable rocket … achieving it would be on a par with what the Wright brothers did. It’s the fundamental thing that’s necessary for humanity to become a space-faring civilization. America would never have been colonized if ships weren’t reusable.”

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“We need to take all heavy industry, all polluting industry, and move it into space. And keep Earth as this beautiful gem of a planet that it is.”

“We’re going to build a road to space so that our kids and their kids can build the future. And we need to do that. We need to do that to solve the problems here on Earth. It’s not about escaping.”