Elon Musk announced earlier this year that his aerospace company, SpaceX, will be shifting its focus to “building a self-growing city on the Moon.” However, scientists recently released a report that laid out how this would be difficult due to the fact that there would not be a sufficient water supply to sustain a city for very long.
Elon Musk and his aerospace company, SpaceX, has been known mainly for their mission to get to Mars and develop a settlement on the red planet. Earlier this year, however, Musk announced that his company would be moving away from that goal, and would be shifting their focus to “building a self-growing city on the Moon.”
Musk posted on X in February:
“SpaceX has already shifted focus to building a self-growing city on the Moon, as we can potentially achieve that in less than 10 years, whereas Mars would take 20+ years.
The mission of SpaceX remains the same: extend consciousness and life as we know it to the stars.
It is only possible to travel to Mars when the planets align every 26 months (six month trip time), whereas we can launch to the Moon every 10 days (2 day trip time). This means we can iterate much faster to complete a Moon city than a Mars city.
That said, SpaceX will also strive to build a Mars city and begin doing so in about 5 to 7 years, but the overriding priority is securing the future of civilization and the Moon is faster.”
Despite these plans, a study published this week in the journal Frontiers in Space Technologies laid out how having a functioning city on the moon would be very difficult to achieve, and the main reason is lack of water.
The study said that although there could be trillions of pounds of water trapped inside tiny glass beads spread across the moon’s surface, it likely won’t be enough to sustain a big city for very long.
Lead study author Martin Elvis, a senior astrophysicist at the Harvard and Smithsonian Center for Astrophysics, spoke to CNN about their findings.
“How big a city could you support on the moon with that water supply? The answer is very surprising.”
Elvis and his colleague, astrophysicist Jonathan McDowell, calculated how long populations of various sizes could potentially last with the estimated 1 billion tons of water they believe is within the moon’s surface; an estimate they said was “generous.”
Considering how water would be used for drinking, hygiene, growing food, rocket fuel, and breathing, a population of 1 million people would finish the water supply in under two and a half years, they wrote in the study.
If the water is efficiently recycled like it is on the International Space Station, however, it would take a city of 1 million people about 100 years to deplete it. “Including always using rather dubious toilets and not doing laundry,” and this behavior is “unlikely to be sustainable, I would think,” Elvis said.
“For such a large investment, a lifetime of about a century seems to fall short of the sustainable, long-term settlement beyond Earth that some advocate.”
They also calculated some smaller city sizes as well. A population of about 100,000 people could survive for 1,000 years “which seems long enough to justify being called sustainable.”
“If you have a small town of only 10,000 people… then you’ve got… 10,000 years’ worth of water, and that starts feeling like, okay, on a 10,000-year timescale, we can find another solution,” McDowell told CNN.
“There is a lot of water in the solar system, including water in the asteroid belt and on the moons of Saturn,” he said. “Maybe in the future, those on the moon could import deliveries of water in the quantities required to sustain a large population. It’s hard to see practically how to do that with current technology, but in the long term, maybe you can do that.”
McDowell proposed that instead of a city on the moon like Musk is proposing, “within 30 years we might have a town on the moon. That would be the way that I would translate what Elon said.”
Astronomer Ian Crawford, a professor of planetary science and astrobiology at Birkbeck, University of London, who was not involved in the study, told CNN how he appreciates the fact that the authors of this research were able to paint a more realistic picture as opposed to Musk and his goal of building an entire city on the moon within the next decade.
“If such settlements are to become established, I think the authors are correct in pointing out that water (or at least hydrogen to manufacture water from oxygen in lunar rocks) will need to be imported,” Crawford stated.
The researchers also wrote in the study that a “Moon Village” of just 1,000 people could be “relatively carefree in [their] use of lunar water.” Crawford also said that in the short term, there is enough water at the lunar poles to support small-scale research outposts of this size “and I think this will be the most likely use in the coming decades.”
“It’s also important to note that the water ice at the lunar poles is of great scientific interest, and we need to be able to study it properly before it is all dug up for water.”
The ice on the moon has accumulated over billions of years and “therefore preserves a chemical and physical record of the environment in which our Earth has existed for all this time, and which led to the development of life on Earth,” Simeon Barber, a senior research fellow at the UK’s Open University, told CNN.
“We should at the very least work out secrets this ice holds for our own evolution and that of our planet — and of other planets — before we consider extracting it for industrial use,” Barber said.
Growing and distributing agriculture will have the most demand for water resources. The study used the World Bank’s estimate that feeding one person for one say requires two to five tons of water.
“Even if people optimize their usage of water, there is still huge uncertainty in how much water there actually is on the moon, but also, how easy is it going to be to extract?” McDowell said.
Barber added that the “extreme cold and extensive darkness” in space can make it an “inhospitable place for robotic or human workers. The water is not in the form of pristine sparkly ice cubes that we could melt and drink; it is likely laced with a cocktail of poisonous chemicals that first must be removed.”
Eric Mastrota is a Contributing Editor at The National Digest based in New York. A graduate of SUNY New Paltz, he reports on world news, culture, and lifestyle. You can reach him at eric.mastrota@thenationaldigest.com.
