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Musk plans city on Mars
June 23, 2017 Sarah Knapton --
A city on Mars with a million inhabitants could be achievable within 50
years, South African space entrepreneur Elon Musk has forecast, as he
laid out plans to turn mankind into a multi-planetary species.----
Nasa has also said it is planning to establish a Mars colony by the
2030s, although it plans to establish a base on the Moon and other
stepping stones first, and the Mars One project, set up by a nonprofit
organisation based in the Netherlands, has proposed to establish a
permanent human colony there by 2027. – The Daily Telegraph
And this is what Slate opinions:
How Plausible Is Elon Musk’s Plan to Colonize Mars?
By Andrew Coates
Musk wants to launch 1,000 spaceships carrying 100 humans each in the
next 40 to 100 years.
NASA via Getty Images
This post originally appeared on The Conversation.
Elon Musk, the founder of SpaceX and Tesla, has released new details of
his vision to colonize 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 multiplanetary species in case
civilization 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.
The idea depends on getting cheaper access to space—the paper says the
cost of trips to Mars must be lowered by “five million percent.” 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
Making fuel on Mars and stations beyond it is something he also
proposes, to make the costs feasible. Experiments toward 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 1 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.
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 zero degrees
Celsius during the day to nearly -120 degrees Celsius 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
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 3.8 billion 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.
For missions farther 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.
That said, aiming high usually means we will achieve something—and
Musk’s latest plans may help pave the way for later exploration.
Future Tense is a partnership of Slate, New America, and Arizona State
Andrew Coates is a professor of physics and the deputy director (solar
system) at the Mullard Space Science Laboratory, University College London.