Hey, Elon Musk, what about toilet paper on Mars?

The SpaceX CEO has some news about his Red Planet plans. And Neal Stephenson, Jonathan Nolan and other science and sci-fi smarties have questions about going interplanetary.

Eric Mack Contributing Editor
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Eric Mack
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Editors' note: Elon Musk has concluded his update on SpaceX's Mars plans. He announced lots of new details about the Mars rocket (aka BFR), promoted the possibility of a lunar base and suggested BFR could fly anywhere on Earth in less than an hour. As for the actual plans to colonize Mars, Musk offered a nice rendering of what a city might look like, but no further details, which means all the questions raised in our story earlier on Thursday still stand. That story is below.  

SpaceX CEO Elon Musk will revise his audacious vision to build a Martian colony when he addresses the International Astronautical Congress in Australia on Friday. But some scientists and futurists may be most interested to hear him talk about toilet paper.

Well, not just TP. There's also dishwashing soap and all the other day-to-day details of life on the red planet that Musk's plan hasn't yet addressed.

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Elon Musk unveiled his master plan for Mars last year in Mexico.

Oscar Gutierrez/CNET

Musk's preliminary outline, unveiled in Mexico last year, offered few specifics on what life will actually be like on Mars. It didn't address how colonists will avoid radiation poisoning or how to supply them with food and clean water.

Musk did make a vague reference to work being done on a potential nuclear-powered sewer and sanitation system for Mars. But his general attitude seems to be that he'll provide rockets and spaceships and everything else will be sorted out along the way.

"We're going to have to get down to the nitty-gritty," Kate Greene, a writer and former laser physicist, told a crowd of space enthusiasts in Santa Fe, New Mexico, in July.

Greene is part of a rare group of humans who, unlike even Musk, can speak from something like experience about living on Mars. In 2013, she was the second-in-command at HI-SEAS, a four-month, simulated Mars mission on the isolated slopes of a Hawaiian volcano. She spoke on a panel at the Santa Fe Institute's (SFI) newest initiative, the Interplanetary Project.

"Day-to-day living on the Mars mission," Greene said, "we were thinking about toilet paper. We were thinking about toilets working well. We were thinking about who's doing the dishes."


Kate Greene in a simulated space suit at HI-SEAS in 2013.

HI-SEAS/Sian Proctor

SFI is an independent research center that studies "complexity science," and the Interplanetary Project borrows from the Star Trek ethos. That is, it makes the assumption that uniting people around a big goal like becoming a multiplanetary species, as Musk puts it, could also help us confront some of our big challenges here on Earth, like tackling climate change and fighting disease.

"The argument is that we're going to solve our problems here by trying to get elsewhere," said Dario Robleto, an artist-in-residence at the SETI Institute.

Santa Fe Institute President David Krakauer expanded on that connection at a gathering of panelists and journalists following this summer's event. "We are bad at predicting how areas of inquiry connect, and the one thing that we do know historically is that very ambitious questions often connect to toilet paper," he said.

It's not that Mars fans are obsessed with bathroom tissue, although it sure came up a lot. To explain, Krakauer cited the example of Galileo, whose observations of the solar system led to a scientific revolution in areas beyond just astronomy. Those advances still affect our everyday lives centuries later, including the engineering knowledge required to mass produce and distribute things like, yes, toilet paper. (It was first introduced by Joseph Gayetty in 1857, thank you very much.)


SpaceX hopes to get started working in that rugged red regolith by 2025. Mars One's mission, based on an odd reality show competition, hopes to get a settlement going by 2032, a year before the goal President Donald Trump has set for NASA to put boots on the planet.

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Pictured from left to right at SFI: CNET's Eric Mack, Santa Fe Institute President David Krakauer and author Neal Stephenson. 

Michael Ferrara/CNET

So far we know Version 2.0 of Musk's Mars plan includes smaller rockets than what he originally revealed last year that could also be used for Earth-orbit missions, making them more economical. The tech tycoon also teased via Instagram this week that "certain aspects of the new design and its applications will be unexpected."

At SFI's Sante Fe event, award-winning astrophysicist Sandra Faber didn't hold back in her evaluation of what drives Musk and other billionaires like Amazon founder Jeff Bezos in the new space race.

"Testosterone," she said, receiving a round of laughter and applause from the crowd.

Famed sci-fi author Neal Stephenson agreed. "It's absolutely testosterone," he said. "And then there's just the strange phenomenon of certain people making a lot of money and having the resources to apply against these kinds of projects."


Neal Stephenson (left), Sandra Faber and David Krakauer on stage at the Lensic Theater in Santa Fe, New Mexico.

Michael Ferrara/CNET

The first Martians

Despite Musk's aggressive Martian timeline, there's certainly no consensus Mars is the best place for a human colony beyond Earth. Bezos seems to prefer the moon, while others, including some former NASA employees, say large orbiting space stations are the way to go.

And even if Musk, the luminaries gathered by SFI and the rest of humanity agree that Mars is a goal worth pursuing, there are still an overwhelming number of questions.

For starters, building an ecosystem from scratch on Mars that can provide food, water and oxygen to support a colony is no small task. Krakauer points out that attempts to create independent ecosystems have typically failed.

A look at Elon Musk's plan to move us to Mars (pictures)

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"We can't create now, with everything we know scientifically, an autonomous ecosystem in lab conditions on the planet Earth with more than five species," he said.

There there's the question of who should go.

Stephenson suggests that in the case of some existential threat to Earth's population, which is one motivation Musk cites for his Mars plan, we would need a colonist selection scheme "that leads to the least warfare and murder on Earth." That would likely come together through a series of political compromises.

Greene points out that women consume fewer calories on average, so an all-female crew might make the most sense on spaceships where weight taken up by food stores is a consideration.

Jonathan Nolan, creator of the HBO series "Westworld" and co-writer of 2014's "Interstellar," raised the notion that perhaps humans may not be our best option.


Jonathan Nolan shared his thoughts on colonizing the universe from the set of "Westworld."

Michael Ferrara/CNET

"So much of what we have to do to explore space would be compromised by our own human frailty," he said in a pre-recorded video. "In any given spaceship, we are the most vulnerable component … We may well want to leave most of the exploring up to our creations."

That means there could be a role for artificial intelligence in becoming interplanetary, an idea that might give Musk pause since he's warned against the perils of AI time and again.

"Maybe AI won't be that terrible," Nolan said. "Maybe it will be wonderful."  

Seeing red in the future

We'll see if Musk addresses any of the more practical Mars considerations on Friday. Perhaps he has a plan to create a crew of Martian colonist cyborgs who communicate using a brain-computer interface like what one of his companies, Neuralink, is developing.

It seems more likely SpaceX and Musk keep focusing on what it's already proven it can do well: build really cool reusable rockets.

Meanwhile, SFI's drive to think about the other aspects of becoming interplanetary are scheduled to continue.

A second panel discussion is set for Oct. 17 and the first annual Interplanetary Festival next June aims to draw space enthusiasts to Santa Fe, where plenty of toilet paper is sure to be available.

Originally published Sept. 28 at 1:15 p.m. PT.
Update at 10:28 p.m. PT:  Added information about Musk's latest Mars announcement.

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