Elon Musk wants to build a “self-sustaining city” on Mars. Experts aren't convinced

Would you board a spaceship built by this man? Elon Musk last week. Image: Getty.

Elon Musk, the founder of SpaceX and Tesla, has released new details of his vision to colonise parts of the solar system, including Mars, Jupiter’s moon Europa and Saturn’s moon Enceladus. His gung ho plans – designed to make humans a multi-planetary species in case civilisation collapses – include launching flights to Mars as early as 2023.

The details, just published in the journal New Space, are certainly ambitious. But are they realistic? As someone who works on solar system exploration, and the European Space Agency’s new Mars rover in particular, I find them incredible in several ways.

First of all, let’s not dismiss Musk as a Silicon Valley daydreamer. He has had tremendous success with rocket launches to space already. His paper proposes several interesting ways of trying to get to Mars and beyond – and he aims to build a “self-sustaining city” on the red planet.

Musk outlining initial plans in 2016.

The idea depends on getting cheaper access to space – the paper says the cost of trips to Mars must be lowered by “five million per cent”. An important part of this will be reusable space technology. This is an excellent idea that Musk is already putting into practice with impressive landings of rocket stages back on Earth – undoubtedly a huge technological step.


Making fuel on Mars and stations beyond it is something he also proposes, to make the costs feasible. Experiments towards this are underway, demonstrating that choosing the right propellant is key. The MOXIE experiment on the NASA 2020 rover will investigate whether we can produce oxygen from atmospheric CO2 on Mars. This may be possible. But Musk would like to make methane as well – it would be cheaper and more reusable. This is a tricky reaction which requires a lot of energy.

Yet, so far, it’s all fairly doable. But the plans then get more and more incredible. Musk wants to launch enormous spaceships into orbit around Earth where they will be refuelled several times using boosters launched from the ground while waiting to head to Mars. Each will be designed to take 100 people and Musk wants to launch 1,000 such ships in the space of 40 to 100 years, enabling a million people to leave Earth.

There would also be interplanetary fuel-filling stations on bodies such as Enceladus, Europa and even Saturn’s moon Titan, where there may have been, or may still be, life. Fuel would be produced and stored on these moons. The aim of these would be to enable us to travel deeper into space to places such as the Kuiper belt and the Oort cloud.

The “Red Dragon” capsule is proposed as a potential lander on such missions, using propulsion in combination with other technology rather than parachutes as most Mars missions do. Musk plans to test such a landing on Mars in 2020 with an unmanned mission. But it’s unclear whether it’s doable and the fuel requirements are huge.

Pie in the sky?

There are three hugely important things that Musk misses or dismisses in the paper. Missions such as the ExoMars 2020 rover – and plans to return samples to Earth – will search for signs of life on Mars. And we must await the results before potentially contaminating Mars with humans and their waste. Planetary bodies are covered by “planetary protection” rules to avoid contamination and it’s important for science that all future missions follow them.

Musk inspecting a heat shield at the SpaceX factory. Image: Steve Jurvetson/Flickr/creative commons.

Another problem is that Musk dismisses one of the main technical challenges of being on the Martian surface: the temperature. In just two sentences he concludes:

It is a little cold, but we can warm it up. It has a very helpful atmosphere, which, being primarily CO2 with some nitrogen and argon and a few other trace elements, means that we can grow plants on Mars just by compressing the atmosphere.

In reality, the temperature on Mars drops from about 0°C during the day to nearly -120°C at night. Operating in such low temperatures is already extremely difficult for small landers and rovers. In fact, it is an issue that has been solved with heaters in the design for the 300kg ExoMars 2020 rover – but the amount of power required would likely be a show-stopper for a “self-sustaining city”.

Musk doesn’t give any details for how to warm the planet up or compress the atmosphere – each of which are enormous engineering challenges. Previously, science fiction writers have suggested “terraforming” – possibly involving melting its icecaps. This is not only changing the environment forever but would also be challenging in that there is no magnetic field on Mars to help retain the new atmosphere that such manipulation would create. Mars has been losing its atmosphere gradually for 3.8bn years – which means it would be hard to keep any such warmed-up atmosphere from escaping into space.

The final major problem is that there is no mention of radiation beyond Earth’s magnetic cocoon. The journey to and life on Mars would be vulnerable to potentially fatal cosmic rays from our galaxy and from solar flares. Forecasting for solar flares is in its infancy. With current shielding technology, just a round-trip manned mission to Mars would expose the astronauts to up to four times the advised career limits for astronauts of radiation. It could also harm unmanned spacecraft. Work is underway on predicting space weather and developing better shielding. This would mitigate some of the problems – but we are not there yet.

Europa. Image: NASA.

For missions further afield, there are also questions about temperature and radiation in using Europa and Enceladus as filling stations – with no proper engineering studies assessing them. These moons are bathed in the strongest radiation belts in the solar system. What’s more, I’d question whether it is helpful to see these exciting scientific targets, arguably even more likely than Mars to host current life, as “propellant depots”.

The plans for going further to the Kuiper belt and Oort cloud with humans is firmly in the science fiction arena – it is simply too far and we have no infrastructure. In fact, if Musk really wants to create a new home for humans, the moon may be his best bet – it’s closer after all, which would make it much cheaper.

The ConversationThat said, aiming high usually means we will achieve something – and Musk’s latest plans may help pave the way for later exploration.

Andrew Coates is professor of physics and deputy director (solar system) at the Mullard Space Science Laboratory, UCL.

This article was originally published on The Conversation. Read the original article.

 
 
 
 

Treating towns as bastions of Brexit ignores the reasons for the referendum result – and how to address them

Newcastle: not all cities are booming. Image: Getty.

The EU Referendum result has often been characterised as a revolt of Britain’s “left-behind” towns and rural areas against the “metropolitan elite”. But this view diverts attention from the underlying issues which drove the Brexit vote – and ironically has diverted policy attention away from addressing them too.

It’s true that a number of big urban authorities, led by London, voted to stay. And overall people living in cities were less likely to vote leave than towns. Setting aside Scottish cities and towns, which both voted very strongly for remain, Leave polled 51 per cent of the vote in English and Welsh cities, compared to 56 per cent in local authorities that include towns. (Consistent data isn’t available below local authority level.)

Yet there is a lot of variation underlying this average across towns. In Boston, 75 per cent voted Leave, and in Hartlepool and Grimsby it was 70 per cent. But at the other end of the scale, there were a number of towns that voted to stay. For example, Leave polled at 49 per cent in Horsham and Harrogate, and 46 per cent in Windsor and Hitchin. In places such as Winchester, Leamington Spa and Bath, the Leave voted amounted to less than 42 per cent of the vote.

What drives this variation across towns? Data from the Centre for Cities’ recent report Talk of the Town shows economic outcomes were the biggest factor – with towns that voted Remain also having stronger economies.

For a start, pro-Remain towns generally have smaller shares of people who were either unemployed or claiming long-term benefit. (This is based on 2011 data, the latest available.)

Towns which voted Remain also had a higher share of jobs in high-skilled exporting businesses – an indication of how successful they have been at attracting and retaining high-paid job opportunities.

And both measures will have been influenced by the skills of the residents in each town: the higher the share of residents with a degree, the stronger the Remain vote.

So the Brexit vote was reflective of the varying economic outcomes for people in different parts of the country. Places which have responded well to changes in the national economy voted to Remain in the EU, and those that have been ‘left behind’ – be they towns or cities – were more likely to have voted to Leave.

This sends a clear message to politicians about the need to improve the economic outcomes of the people that live in these towns and cities. But the irony is that the fallout from the Brexit has left no room for domestic policy, and little progress has been made on addressing the problem that, in part, is likely to have been responsible for the referendum outcome in the first place.

Indeed, politicians of all stripes have seemed more concerned about jostling for position within their parties, than setting out ideas for domestic policy agenda. Most worryingly, progress on devolution – a crucial way of giving areas a greater political voice – has stalled.


There was talk earlier this year of Theresa May relaunching her premiership next summer focusing on domestic policy. One of her biggest concerns should be that so many cities perform below the national average on a range of measures, and so do not make the contribution that they should to the national economy.

But addressing this problem wouldn’t ignore towns – quite the opposite. What Talk of the Town shows is that the underperformance of a number of cities is bad not just for their residents or the national economy, but also for the residents in surrounding towns too. A poorly performing neighbouring city limits both the job opportunities open to its residents and impacts on nearby towns’ ability to attract-in business investment and create higher paid jobs.

This isn’t the only factor – as the last chart above suggests, addressing poor skills should be central to any serious domestic policy agenda. But place has an influence on economic outcomes for people too, and policy needs recognise that different places play different roles. It also needs to reflect the importance of the relationships between places to improve the access that people across the country have to job opportunities and higher wages.

The Brexit vote didn’t result from a split between cities and towns. And if we are to address the reasons for it, we need to better understand the relationship between them, rather than seeing them as opposing entities.

Paul Swinney is head of policy & research at the Centre for Cities, on whose blog this article first appeared.

Read the Centre’s Talk of the Town report to find out more about the relationship between cities and towns, and what this means for policy.