EDITORIAL: Elon Musk unveils another ambitious vision

Elon Musk made another big splash last week with the announcement that he hopes to send a manned spacecraft to Mars by 2022. Mr. Musk, the ambitious and media-savvy founder of SpaceX and Tesla, told an audience in Australia that his company will build the world’s most powerful rocket to achieve his goal.

SpaceX “seeks to create a single fleet of super-powered rockets and spacecraft able to serve commercial satellite operators, U.S. government customers and Mr. Musk’s own dreams of deep space exploration,” The Wall Street Journal reported. The cost of a mission to Mars could reach $10 billion, experts believe.

“I think we have figured out a way to pay for it,” Mr. Musk said. “We think we have a way to do it.”

Mr. Musk has a history of grandiose pronouncements. He hasn’t always met his goals. In addition, many of his endeavors, particularly Tesla, rely heavily on federal and state taxpayer subsidies. If he has found a way to privately fund such a space mission, more power to him. A Mars landing would be one of mankind’s greatest achievements.

But other issues aside, the biological realities must be addressed for the attempt to succeed. A round-trip flight to Mars would take up to 30 months. That’s far longer than any human has been in space before. How astronauts would react physically and psychologically remains unclear.

“Extended stays in zero-g cause bone and calcium degradation, muscle loss and a recently identified issue that may stem from swelling in the optic nerve,” a 2013 report in Wired magazine notes. “Left unchecked, astronauts arriving on Mars could be weak, brittle-boned and possibly blind.”

In his presentation, Mr. Musk focused primarily on the technological and financial barriers to his goal. In the end, however, ensuring that the crew can withstand the physical and mental challenges of more than two years in space represents the most significant hurdle to any manned Mars mission.