A dust storm on Mars. (Image: Ren Wicks/NASA/JPL-Caltech)
In 2016, this is what one vision of sending humans to Mars looks like:
At the 67th International Astronautical Congress, in Guadalajara, Mexico, the billionaire inventor Elon Musk gave a speech that was more anticipated than any other he's given. Musk has an incredible talent for making people feel like humanity is on the cusp of a new future (solar power! rad self driving cars! space travel!) and in this speech, titled “Making Humans a Multiplanetary Species," he explained, in detail, the vision summarized in the video above—he explained how he thought humanity could get to Mars and create a "self-sustaining city" there.
To get to Mars, aiming for a cost of around $200,000 per person, Musk said, would require four main technologies: reusable rockets, in-orbit refueling of spaceships, Mars-based propellant production, and the right propellant. The reusable rocket could return to earth in about 20 minutes, and it would take off three to five times to fill the tanks of the Mars-bound spaceship in orbit. Once flights started—and he's envisioning fleets of ships headed out—each could have at least hundred people on it and eventually 200 or more. He estimated that it would take 40 to 100 years to create a fully self-sustaining city on Mars, and that ultimately, trips to Mars could take as little as 30 days.
"If things go well," he said, this plan could send a ship to Mars in the "ten-year timeframe."
How revolutionary is this? Much of what Musk described is so ambitious that many smart people have doubts about its feasibility—just creating reusable rockets is a gargantuan task. But it's also familiar, in some ways. Elements of Musk's plan, including the image of a fleet of ships launching from Earth, have been part of visions of Mars colonization ever since scientists started seriously thinking about the possibility, in the 1950s.
Here are a few of the past visions of how humans will reach Mars and stay there.
1950s: Wernher von Braun’s Mars Project
The first detailed vision of American spaceflight to Mars was the brainchild of Wernher von Braun, the former Nazi scientist who worked for NASA after World War II. His 1952 book, The Mars Project, became the first widely disseminated Mars colony plan, in the form of a 1954 article in Collier’s Magazine and a Disneyland film.
In this plan, von Braun imagined that a fleet of 10 massive spaceships, assembled in space, would carry 70 people, along with the supplies needed to survive. In the Collier’s article, he wrote that space taxis would ferry people between the convoy’s ships and that one of the concerns of long-distance space exploration—radiation exposure—could be assuaged by the invention of “a drug which will enable men to endure radiation for comparatively long periods of time.”
The Mars Excursion Module, as imagined in the 1960s. (Image: Philco/NASA)
Once the convoy reached Mars, an initial exploration party would land on the planet’s smooth ice caps—the most suitable runway—and travel towards the more habitable equator. Once a better landing strip was constructed, two more ships would travel to the planet’s surface. On Mars, the explorers would live in inflatable, pressurized spheres about 30 feet across and mounted on tractors for mobility.
Estimated length of journey: 8 months
Length of stay: More than a year
Crew size: 70
Estimated timeline: Mid-21st century
1980s: The Mars Underground and the Case for Mars
A model for circulating space ships. (Image: Pioneering the Space Frontier/NASA)
In the late 1970s, after the excitement over the first manned mission to the moon had passed, a small group of scientists got excited about visiting Mars next. “The Mars Underground,” as they were called, started examining the “habitability of Mars” and convened a series of conferences to make “the Case for Mars.” By the mid-1980s, sending people to Mars had become a key feature of Pioneering the Space Frontier, a federal report on the future of space exploration.
A Mars base as imagined in the 1970s. (Image: Robert McCall/www.McCallStudios.com)
One of the major features of this plan was a system of spacecraft that would travel in a loop between the two planets—like “ocean liners on a fixed route.” They would stop at transfer points close to Earth and to Mars, but would never land themselves. A permanent Mars base would be built with technology first tested on the Moon, and crews would cycle out, much like on the ISS, on regular schedules.
Estimated travel time: 6 months
Length of Mars stay: about one year
Crew size: 17 on the cycling ship, 20 on the Mars Base
Estimated timeline: 2020s or so
1990s: Robert Zubrin and Mars Direct
A 1989 concept sketch of a Mars mission. (Image: Les Bossinas/NASA)
All the momentum that Mars advocates created in the ‘80s, though, crashed in the early ‘90s when the first Bush administration looked at the potential costs of this project and blanched. But one Mars-minded man, Robert Zubrin started developing a new—and cheaper—vision for reaching Mars, in which lunar bases and exploration were cut out of the plan and ships were sent directly to Mars.
Mars, now with underground vegetable farms. (Image: NASA Ames Research Center)
Zubrin’s plan evolved over many years: a key feature became small, cylindrical habitat units that would detach from the spacecraft that brought the explorers to Mars. There would be a dedicated section for science, for health and exercise, and a small lounge. Mars colonization would happen in stages—the first crews would stay for 18 months, but those missions could be extended for longer periods as ships started making regular journeys. The habitat units could gather into a small village on the surface of the planet.
Estimated travel time: 6 months, minimum
Length of stay: 18 months (can extend to four or more years)
Crew size: 4
Estimate timeline: Originally, 1999
Now that the early decades of the 21st century have arrived, it is looking more likely than ever before that humans will go to Mars. Besides Musk's plan, NASA is aiming to send astronauts to Mars around 2035, and Congress has actually taken steps to fund that vision. Mars One is still winnowing down applicants to crew a one-way trip to the Red Planet. One day after Musk's address at the IAC, Lockheed Martin is presenting its ideas for a "Mars Base Camp." Blue Origin, the space company created by Jeff Bezos, of Amazon, is thinking about Mars, too.
If we do arrive on Mars, that's not the end of the story. Notably, Musk's talk concentrated on how to get to Mars, not what exactly would happen once people reached their destination. But at the end of the video Space X released, the dry, red planet spin until there's splotches of blue and green—a hint at another idea Musk has talked about. Once we're there, he thinks, we should terraform the whole planet.