“My guess is we will never go to Mars with the engines that exist on any of those three rockets unless we truly have to,” he said.
He continued, “I don’t think those are a practical way to send people to Mars because they’re dangerous and it takes too long.”
Hadfield took three trips into space between 1995 and 2013. During a mission to the International Space Station in 2001, he helped install a mechanical arm outside the station, becoming the first Canadian to take a spacewalk. Hadfield’s caution may be surprising, given that he has himself taken such risks in space.
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Hadfield noted “the technology that took us to the moon back when I was just a kid . . . can take us to Mars,” but that “the majority of the astronauts that we send on those missions wouldn’t make it.” He thinks liquid-fuel rockets currently in development, including NASA’s Space Launch System and SpaceX’s BFR, will still pose unacceptable risks.
He compared the prospect to trying to cross an ocean in a canoe. “I think we need some more improvements in technology before we’ll cross the oceans that are between us and Mars in any sort of practical way.”
Hadfield tentatively suggested that ion propulsion, nuclear power, or even the manipulation of gravity might be safer.
But those technologies are either highly speculative, or still in the early stages of development. In the meantime, instead of putting human lives on the line, Hadfield had another idea.
“Why wouldn’t we just send robots for quite a while until we learn a lot more about Mars?” he said.