The colleagues state — in one of 55 articles in the issue devoted to exploring Mars — that humans must begin colonizing another planet as a hedge against a catastrophe on Earth.
Mars is a six-month flight away, possesses surface gravity, an atmosphere, abundant water, carbon dioxide, and essential minerals. They propose the missions start by sending two two-person teams, in separate ships, to Mars. More colonists and regular supply ships would follow.
The technology already exists, or is within easy reach, they wrote.
A NASA official said the space agency envisions manned missions to Mars in the next few decades, but that the planning decidedly involves round trips.
President Obama informed NASA in April that he “ ‘believed by the mid-2030s that we could send humans to orbit Mars and safely return them to Earth. And that a landing would soon follow,’ ’’ said agency spokesman Michael Braukus.
Nowhere did Obama suggest the astronauts be left behind.
“We want our people back,’’ Braukus said.
Retired Apollo 14 astronaut Ed Mitchell, who walked on the moon, was also critical of the one-way idea. “This is premature,’’ Mitchell wrote in an e-mail. “We aren’t ready for this yet.’’
Davies and Schulze-Makuch say they are not proposing a “suicide mission.’’
“The astronauts would go to Mars with the intention of staying for the rest of their lives, as trailblazers of a permanent human Mars colony,’’ they wrote, while acknowledging the proposal is a tough sell for NASA, with its intense focus on safety.
They think the private sector might be a better place to try their plan.
“What we would need is an eccentric billionaire,’’ Schulze-Makuch said. “There are people who have the money to put this into reality.’’
Indeed, British tycoon Richard Branson, PayPal founder Elon Musk, and Jeff Bezos, chief executive of Amazon.com Inc., are among the rich who are involved in private space ventures.
Isolated humans in space have long been a staple of science fiction movies, from “Robinson Crusoe on Mars’’ to “2001: A Space Odyssey’’ to a flurry of recent movies such as “Solaris.’’
Psychological profiling and training of the astronauts, plus constant communication with Earth, would reduce severe mental strains, the two scientists said.
“They would in fact feel more connected to home than the early Antarctic explorers,’’ according to the article.
But the mental health of humans who spent time in space has been extensively studied. Depression can set in, people become irritated with each other, and sleep can be disrupted, the studies have found. The knowledge that there is no quick return to Earth could make that worse.
Schulze-Makuch and Davies contend that Mars has abundant resources to help the colonists become self-sufficient over time. The colony should be next to a large ice cave, to provide shelter from radiation, plus water and oxygen, they wrote.
They believe the one-way trips could start in two decades.
“You would send a little bit older folks, around 60 or something like that,’’ Schulze-Makuch said.