NASA Mars bombshell: Space agency astronaut reveals ‘greatest obstacles’ for Mars mission

He told Express.co.uk: “The brief answer to whether humans can survive a journey to, and live on, Mars is ‘probably’ – the question is how successfully they will do so.

“We see some pretty changes in human biology – large enough that we would want to mitigate them, at least in part.

“And we are not sure we have the strategies in place just yet.”

The NASA astronaut revealed the issues range from the physiological, biological and even psychological.

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