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A million people in 40 to 100 years: SpaceX unveils plan to colonize Mars

Posted by Jason Davis

27-09-2016 22:46 CDT

Topics: commercial spaceflight, human spaceflight

Today at the 67th International Astronautical Congress in Guadalajara, Mexico, SpaceX CEO Elon Musk revealed his much-anticipated plan to send humans to Mars. 

The presentation, which was streamed live, lasted about an hour. It was followed by a question-and-answer session, during which space news reporters split microphone time with eccentric fans, self-promoters and even one attendee attempting to solicit a kiss from Musk himself. (An impromptu press conference with media was held later.)

Musk's plans are so ambitious, they nearly defy analysis. Of all the modern private space firms claiming they will ferry tourists to orbit, mine asteroids and set up commercial space stations, SpaceX may stand alone in its ability to present such a staggeringly audacious plan and still be taken seriously. Even NASA might raise more objections if it were to drop an equally zealous version of its current Journey to Mars plans.

Put simply, Musk wants to colonize Mars. Humanity, he believes, must become an interplanetary species before some future calamity wipes our presence from the Earth. 

Whereas NASA's humans-to-Mars plans envision an Antarctica-like research station with a rotating crew of astronauts, Musk wants to have a million people there in 40 to 100 years. He stopped short of saying he wanted to terraform the planet, but frequently alludes to the possibility; SpaceX's new video on its Mars transportation system ends by showing the Red Planet spinning into an Earth-like orb.


SpaceX Interplanetary Transport System

The plan

Musk envisions up to 100 Mars-bound colonists boarding an oblong spacecraft perched atop a massive rocket at Kennedy Space Center's launch pad 39A. The rocket's width would be 12 meters; the entire stack would top 122 meters. By comparison, the Saturn V was 111 meters tall and 10 meters wide at the bottom; NASA's Space Launch System will debut at 98 meters tall and 8.4 meters wide.

The rocket would be powered by a staggering 42 engines, generating 28.7 million pounds of thrust at liftoff. That's almost exactly four times more powerful than the Saturn V, which had just five engines. The only other vehicle to attempt an engine configuration on this scale was the Soviet N-1 moon rocket, which had 30 engines and was destroyed four times in four launch attempts.

The booster rocket blasts the Mars colonists into a parking orbit before returning directly to its launch pad for an upright landing. Next, a pad crane lifts a nearby propellant tanker—shaped similarly to the colonists' spaceship—onto the reused booster. The rocket launches again, sending the tanker into orbit to rendezvous with the passenger ship. After a fuel transfer, it's on to Mars for the colonists, while the booster and tanker return to Florida to repeat the process.

Musk's diagrams showed an intention to reuse the booster 1,000 times and the fuel tanker 100 times. That sort of reusability is utterly without precedent; the most re-flown spacecraft of all time is space shuttle Discovery, which completed 39 missions in 27 years. Discovery and its sibling shuttles could carry a crew of seven into low-Earth orbit for a couple weeks; the Mars colonial spaceship would spend between 90 and 150 days en route to Mars.

The cost

Musk estimated it would take $10 billion to develop his transport system. That's optimistic, but in the realm of possibilities. In 1972, NASA estimated space shuttle development would cost $5.15 billion—roughly $30 billion in today's dollars (not counting cost overruns).

SpaceX's estimated cost to build a single booster, tanker and transport ship is $560 million dollars. After the Challenger disaster, NASA paid $1.7 billion for space shuttle Endeavour. By the time the shuttles retired in 2011, it was estimated the program had cost of $209 billion.

Whatever the price tag, it remains to be seen exactly how SpaceX would pay for all this. During the presentation, Musk jokingly used a South Park reference (underpants gnomes) before saying the company would continue focusing on its core business of launching satellites and sending NASA crew and cargo missions to the International Space Station.

At the moment, it can do neither. Earlier this month, a Falcon 9 rocket exploded during a routine propellant filling operation, marking the company's second payload loss in 15 months. SpaceX has yet to find the cause of the accident, though they recently said the problem appeared to have originated in the rocket's upper stage helium pressurization system (notably, Musk said the company's new rocket booster would be autogeneously pressurized and not require such a design).

SpaceX interplanetary transport system on launch pad


SpaceX interplanetary transport system on launch pad

Ramping up

Right now, Musk estimates less than 5 percent of his company is working on the Mars project. What few employees are appear to be working overtime; Musk used the phrase "seven days a week" days to describe recent efforts to complete a carbon fiber liquid oxygen tank and test-fire the company's new Raptor engine.

That 5 percent figure will likely need to increase—soon. While conceding he doesn't always stick to promised timelines, Musk offered a diagram that showed booster tests starting in 2019, orbital flights kicking off in 2020, and trips to Mars beginning in late 2022. In the meantime, the first Red Dragon—a Mars-capable version of the company's upcoming Crew Dragon capsule—is still scheduled to fly in 2018. Musk also said the Falcon Heavy rocket, which is essentially three Falcon 9 vehicles strapped together, would debut early next year.

Despite all the details revealed in today's presentation, many questions remain: What kind of life support systems will be used? Where will SpaceX build all this? How will the colonists stay healthy on their trip? And on Mars? What kind of infrastructure will support them there? Will SpaceX build a NASA-esque Deep Space Network for Mars communications? The list goes on and on.

There are also ethical considerations. NASA builds its spacecraft with the mentality that "failure is not an option," always keeping in mind tragedies like Columbia, Challenger and Apollo 1. Musk, on the other hand, openly admits people are likely to die.

And what about planetary protection? Will SpaceX's vision of the future clash with detractors that wish to keep the planet pristine?

Since the moon landings, we have largely trusted NASA to decide how, when—and to some degree, why—humanity should make its first giant leap to another world. Despite the very real questions about whether America's space agency can sustain the political and programmatic momentum needed to land humans on Mars in the mid-2030s, they stand alone atop the list of possible contenders.

Until perhaps now.

Elon Musk's claim that he can develop a million-person-strong colony on Mars in 40 to 100 years deserves scrutiny. But there's no doubt he's going to try, and we're likely to see a lot of fantastic innovations along the way.

Musk's plans are also likely to spark the imaginations of the next generation of scientists and engineers that will pick up the baton, should SpaceX fall short. In what can sometimes feel like a world full of impossibilities, SpaceX is trying to reset the idea of what is possible.

Goodbye, Earth


Goodbye, Earth
Bearing 100 colonists, SpaceX's Interplanetary Transport System departs Earth for Mars.

Thanks to Casey Dreier for suggesting the last line.

See other posts from September 2016


Or read more blog entries about: commercial spaceflight, human spaceflight


Red: 09/28/2016 03:29 CDT

I longed to hear more details, especially how the Red Dragons would be utilized beyond perfecting EDL. Still, Elon was inspiring, if a touch over-optimistic. His scheme itself seems plausible. My faith in NASA died some time ago in regards to human spaceflight, specifically at Space Camp where I was openly told "oh we're not going to Mars until 2020" (back in the early 1990s). NASA, whether you view it as lack of will and motivation or having its hands bound by politics, can't repeat Apollo in the modern climate. If it could, we would have been to Mars by now. If not his plan, something like Elon Musk's plan may materialize. We may see entities akin to the East Indies Company reaching out in place of NASA.

Stephen: 09/28/2016 04:47 CDT

The plan sounds impressively ambitious. Whether it actually eventuates though we will have to wait and see. Thus far none of the space entrepreneurs who keep claiming to be working on vessels to put humans in orbit has thus far done so yet here is Musk wanting to go way beyond that goal! One thing that worries me: the refuelling in orbit bit. On the one hand that is certainly a neat idea. On the other hand just exactly how safe would that be? AFAIK the airlines are not allowed to refuel their airliners with passengers onboard. In fact back in the days when a trip between Australia and Europe required a couple of refuelling stops, we passengers were required to get off the plane and go into the terminal while they did so. Yet that video suggests Musk’s rockets will be refuelling with passengers onboard! Call me overly cautious, but given the tendency of Musk’s rockets to go KA-BOOM that sounds like an accident waiting to happen. In that context, this line “Musk, on the other hand, openly admits people are likely to die” is not exactly encouraging! Killing 100+ people in a single large KA-BOOM would place a large dent in even Musk’s ambitious plans, especially when (given the likely price tag of tickets on his vessels: “less than $200,000” on up) most if not all that 100+ are most likely to be multi-millionaires, at least for the foreseeable future, whose heirs are not likely to be short of lawyers. That suggests that those who are dying to go to the Red Planet (so to speak) might want to wait a decade or two until Musk has ironed out the bugs. Who knows? By then, and with any luck (and the occasional KA-BOOM) his rockets may have thinned out the multi-millionaire herd sufficiently to force him to lower his ticket prices enough to allow more ordinary folks to go (at least without first liquidating most of their assets). :-)

Tim: 09/28/2016 02:34 CDT

While I am all in favour of Elon Musk's ambitious plans, I do think that the number of colonists is optimistic. To use an analogy, Mars is like Antarctica but with a thin toxic atmosphere and significantly more radiation. Furthermore, there's an awfully long supply chain for Mars and even Antarctica only supports about 4,000 science and technical staff in summer and 1,000 or so such staff in winter. A more realistic large estimate might be tens of thousands of scientists and colonists even after several decades given the huge challenges of surviving on the barren planet that is Mars. PS I loved the old stories of Mars from Ray Bradbury and Leigh Brackett and I only wish that, like their tales, Mars had been at least naturally semi-habitable.

HaHaRich!: 09/28/2016 10:48 CDT

Tim you are also forgetting to mention the perchlorate dust that will kill anyone who inhales it by destroying their thyroid

txfromwi: 09/29/2016 12:19 CDT

If folks are considering terraforming Mars, I would suggest that we start with Earth first and begin removing those unwanted 50ppm or so of CO2.

Stephen: 09/30/2016 01:14 CDT

@txfromwi:: FYI we're already terraforming Earth. It's called (man-made) global warming.

Vidar: 09/30/2016 07:38 CDT

I like the Idea ! I am sure there will be loads of changes and millions of ideas to get to Mars and Start a World there. I think everything is POSSIBLE. Build up Monolitic Dome´s with underground tunnels for a Start .. Aquaponic Food Systems... aso... Everything sounds good .. everything has to be tryed out ... Question is : Are there enough People around who would go on a Suicide Misson ? Is there a way to launch Robots to Build ( 3 D Print ) Houses ( dome ) ?

john: 10/01/2016 10:02 CDT

If we go on at our present rate and destroy the Earth, we will need Mars for the survival of the human race.

harukichou: 10/02/2016 09:48 CDT

We can not even colonize Detroit.

Bob Ware: 10/02/2016 06:48 CDT

Paraphrasing the former President John Fitzgerald Kennedy about going to the moon in part; If this task should be so difficult to partake in', then he added in closing that comment, in his judgement it would be better not to go at all. I say 'go.'

Torbjörn Larsson: 10/11/2016 12:04 CDT

Some nitpicks: - On engine numbers. SpaceX will attempt to have Falcon Heavy launching before the ITS booster since the Red Dragon missions depend on it. They will use 27 engines at launch, roughly emulating N1. - On colony plans, SpaceX doesn't plan to develop a colony, but to provide the transport service for people who wants to build colonies. - On NASA ethic, they do admit a certain accumulated death rate for missions. Perhaps 1-2 % of launched crew dies at launch, and the limit for life long accumulated death risk due to radiation is 5 %, et cetera. My beef was at first glance the craft crew volume looks small compared to a person, But amazingly it is actually twice the length and many times the crew volume of the largest transport to the Jamestown colony for a mission of half the duration. They can do this! Even Antarctica has the Argentine colony. On planetary protection, if memory serves it is the responsibility of US to craft laws regulating their citizens. So it will be solved one way or another. [The PS text challenge was "living", which is oddly appropriate.]

Torbjörn Larsson: 10/11/2016 12:20 CDT

Ah, I forgot to mention that the SLS projected cost to Mars is some 30 GUSD for the whole system, making the ITS cost of 10 GUSD seem correct. @Stephen: "that video suggests Musk’s rockets will be refuelling with passengers onboard!" They will have years to perfect in space refuel techniques, and if it isn't doable the system fails. Though I note that Musk put this as a yellow warning in the metalox assessment.

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