The first people who fly with SpaceX to Mars should be OK with the possibility that the decision could cost them their lives, company founder and CEO Elon Musk said.

SpaceX aims to ferry 1 million people to the Red Planet over the next 50 to 100 years using the Interplanetary Transport System (ITS), a rocket-spaceship combo that Musk unveiled Tuesday (Sept. 27) during a talk at the International Astronautical Congress (IAC) in Guadalajara, Mexico. (Well, he unveiled the ITS in concept; neither vehicle has been built yet.)

Musk painted a picture of a not-too-distant future in which 1,000 or more ITS spaceships, each loaded up with 100 or 200 settlers, zoom off toward Mars simultaneously from Earth orbit. But it's naïve to expect that everything will work perfectly from the start, he said. [Images: SpaceX's Interplanetary Transport for Mars Colonization]

"I think the first journeys to Mars are going to be really very dangerous. The risk of fatality will be high; there's just no way around it," Musk said at the IAC, adding that, for this reason, he would not suggest sending children on these flights.

"It would be, basically, 'Are you prepared to die?' If that's OK, then, you know, you're a candidate for going," he said.

Musk said he'd like to go to Mars, but it's unclear if he'll be among the Red Planet vanguard. In a teleconference with reporters Tuesday after the IAC talk, he said he wasn't sure if he'd be aboard the first-ever Mars colony ship, which may be called "Heart of Gold" after a vehicle in Douglas Adams' "Hitchhiker's Guide to the Galaxy."

"I would definitely need to have a very good succession plan, because the probability of death is quite high on the first mission, and I'd like to see my kids grow up and everything — so, some pros and cons there," he said.

Musk has long said that he founded SpaceX in 2002 chiefly to help humanity colonize Mars. Becoming a multiplanet species would serve as an insurance policy, minimizing the risk of humanity's extinction should something terrible happen on Earth, he has said.

Musk reiterated that argument during the IAC presentation Tuesday. But he also put forth another reason why settling Mars is worth the trouble and the treasure and the risk.

"It would be an incredible adventure; it would be the most inspiring thing that I can possibly imagine," he said. "Life needs to be more than just solving problems every day. You need to wake up and be excited about the future, and be inspired and want to live."

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