A new report sponsored by NASA has put Elon Musk on the defensive about his plans for building a community on Mars. Now, the billionaire tech titan and the leading government space agency are at odds on social media about how possible it is for Mars to be habitable by humans in the near future.
This week, NASA said the idea of making the surface of Mars habitable in the near future is not realistic. "Science fiction writers have long featured terraforming, the process of creating an Earth-like or habitable environment on another planet, in their stories. Scientists themselves have proposed terraforming to enable the long-term colonization of Mars," NASA says in a written statement released Monday.
However, it adds, "transforming the inhospitable Martian environment into a place astronauts could explore without life support is not possible without technology well beyond today's capabilities."
NASA references a study by Bruce Jakosky of the University of Colorado, Boulder, and Christopher Edwards of Northern Arizona University, Flagstaff, Arizona, which appeared in Nature Astronomy on July 30. Professor Jakosky is the principal investigator on NASA's mission to study the atmosphere around Mars, the MAVEN (Mars Atmosphere and Volatile Evolution) mission, and the study was funded by NASA.
The atmosphere surrounding Mars is too thin and the temperature too cold to allow for liquid water. One way to make terraforming Mars possible, some suggest, is by releasing carbon dioxide from the polar ice caps and soil on Mars to create an atmosphere thick enough to warm the planet up and make liquid water possible.
There is just not enough carbon dioxide trapped in various sources in Mars to make this possible, the NASA-sponsored study says.
"Our results suggest that there is not enough CO2 remaining on Mars to provide significant greenhouse warming were the gas to be put into the atmosphere; in addition, most of the CO2 gas is not accessible and could not be readily mobilized. As a result, terraforming Mars is not possible using present-day technology," said Jakosky in a written statement released by NASA about the study.
But billionaire SpaceX CEO Musk says the red planet can be made hospitable to humans, and he's already planning for the reality.
On stage at the 2017 International Astronautical Congress in Adelaide, Australia, in September, Musk said he wants to land at least two cargo ships on Mars by 2022. And, by 2024, Musk says he wants to sends passengers to Mars.
"I feel fairly confident that we can complete the ship and be ready for a launch in about five years. Five years seems like a long time to me," Musk said in September. "Then build up the base, starting with one ship, then multiple ships, then start building out the city, then making the city bigger, and even bigger. And yeah, over time terraforming Mars and making it really a nice place to be."
Discovery Magazine covered this week's report from NASA with a cheeky headline: "Sorry, Elon. There's not enough CO2 to terraform Mars." Musk responded to a tweet featuring the article. "There's a massive amount of CO2 on Mars adsorbed into soil that'd be released upon heating. With enough energy via artificial or natural (sun) fusion, you can terraform almost any large, rocky body," Musk says.
For a follow-up story with the headline, "No Seriously, Elon. You Can't Just Nuke Mars (We Asked)," Discovery Magazine brought Musk's contention to Jakosky, Edwards and Roger Wiens, a scientist at Los Alamos National Laboratory.
"When you're thinking about a technology far into the future, you can think about anything you like and imagine it's feasible," Jakosky tells Discovery. "That's why we stuck with today's technology — things we actually know how to do."
Musk continued to protest, and he provided a link to a study featuring a NASA scientist with the opposite perspective.
"It is concluded that a drastic modification of Martian conditions can be achieved using 21st century technology. The Mars so produced will closely resemble the conditions existing on the primitive Mars. Humans operating on the surface of such a Mars would require breathing gear, but pressure suits would be unnecessary," says the study shared by Musk, which is authored by Christopher P. McKay of the NASA Ames Research Center and Robert M. Zubrin of Martin Marietta Astronautics. "With outside atmospheric pressures raised, it will be possible to create large dwelling areas by means of very large inflatable structures. Average temperatures could be above the freezing point of water for significant regions during portions of the year, enabling the growth of plant life in the open. The spread of plants could produce enough oxygen to make Mars habitable for animals in several millennia."
Zubrin chimed in on Twitter after Musk shared the study he wrote with McKay and said there is indeed enough CO2 on Mars.
In a follow-up statement, NASA hedged its bets, clarifying that the technology for terraforming Mars is not available yet.
"Loss of atmosphere to space is the largest 'sink' for CO2, accounting for a large fraction of any early CO2 and making it unavailable on the planet today," NASA tells CNBC Make It in an emailed statement. "While researchers feel future technology in the coming decades will allow for such methods to terraform, the first step is to better understand Mars before any humans live and work there."
Jakosky says he has seen the responses from Musk. "I look forward to seeing his (and Bob Zubrin's) analyses in their full detail. Open and honest discussion of the scientific and technical issues is always a healthy thing," he tells CNBC Make It.
Musk's rocket and spacecraft company, SpaceX, depends on building a reality where it is possible for humans to live on other planets. "The company was founded in 2002 to revolutionize space technology, with the ultimate goal of enabling people to live on other planets," SpaceX says on its website.
An inspired life depends on humans moving beyond Earth, says Musk. "I'm going to talk more about what it takes to become multiplanet species. And just a brief refresher on why this is important. I think fundamentally the future is vastly more exciting and interesting if we're a spacefaring civilization and a multiplanet species than if we're or not," Musk said at the 2017 International Astronautical Congress.
"You want to be inspired by things. You want to wake up in the morning and think the future is going to be great. And that's what what being a spacefaring civilization is all about. It's about believing in the future and thinking that the future will be better than the past. And I can't think of anything more exciting than going out there and being among the stars. That's why," Musk said.
The red planet, Musk says, is the best option for life beyond Earth.
"SpaceX, or some combination of companies and governments, needs to make progress in the direction of making life multi-planetary, of establishing a base on another planet, on Mars — being the only realistic option — and then building that base up until we're a true multi-planet species," Musk says in a 2013 TED Talk.
For NASA, the feasibility of getting Mars is important, too. In December, President Donald Trump told the space agency to prioritize reaching and doing more with the red planet.
"The directive I am signing today will refocus America's space program on human exploration and discovery. It marks a first step in returning American astronauts to the Moon for the first time since 1972, for long-term exploration and use. This time, we will not only plant our flag and leave our footprints — we will establish a foundation for an eventual mission to Mars, and perhaps someday, worlds beyond," Trump said.
The fourth goal of NASA's Mars Exploration Program involves preparing for human exploration. To do this, NASA aims to "obtain knowledge of Mars sufficient to design and implement sustained human presence at the Martian surface with acceptable cost, risk, and performance," the government agency's website says.
Specifically, NASA scientists are working to better understand conditions on the ground — and in the air.
"The science teams for the flight missions are tasked with analyzing their measurements and determining the implications for understanding Mars as a planet and for understanding Mars in the context of the rest of the solar system (and, now, other planetary systems)," Jakosky tells CNBC Make It. "Our analysis was part of our ongoing task of trying to understand the volatile inventory of Mars, its history, and the history of the planet's climate. We are focused on, among other things, determining how much CO2 Mars has had, how much has been lost to space (derived from data from the MAVEN mission), how much has been locked beneath the surface (from the [Mars Reconnaissance Orbiter] mission), and how it can interact or exchange with the atmosphere."
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