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they fly out on, he says, would stay on Mars to provide future
accommodation. A second ERV would be launched at the
same time to provide back-up and, if all goes well, would be
ready to bring the next team home two years later. In this
way, a series of return trips would build up a number of living
spaces on Mars for longer stays in the future. And because
most of the fuel for the return trip would be made on Mars,
Zubrin believes huge energy and cost savings could be made.
NASA’s own plans are more cautious. They involve moving
long-duration human missions out from the ISS to orbit the
Moon over the next 13 years, while continuing the scientificmultiple engines mean that even
if some of them failed, a mission
could continue. The first test-
firing of a Raptor engine went
well in September 2016.
The launch rocket would be the
most powerful ever built – taller
than the Saturn V of the Apollo missions and massively more
capable. It could launch 300 tons of cargo into orbit and return
to land vertically on the launch pad, ready for reuse with
minimal maintenance. As with the Mars Society plan,
economies come from fuelling the outward craft in orbit
and manufacturing fuel for the return trip on Mars itself.
But Musk has his sights set on more than just cargo
delivery; he has visions of a Mars colony, and a fleet of
hundreds of such craft in the next century. He says he
wants to ‘create a self-sustaining civilisation, not an outpost,
so humans can become a multi-planetary species’.exploration of Mars; followed up with cargo delivery and an
unmanned sample-return mission in the late 2020s. But,
they say, it won’t be before the early 2030s that humans orbit
Mars, let alone land on the planet. Meanwhile, Elon Musk,
former PayPal entrepreneur and founder of SpaceX, has his
own plans. He already has a NASA contract for delivering
supplies to the ISS and hopes to be able to deliver cargo to
Mars in 2018, in preparation for a human mission in the 2020s.
‘Mars is something we can do in our lifetimes,’ he says.Xtra terrestrial
The SpaceX concept has been developed in some detail. Its
present Falcon 9 rocket and Dragon capsule are already flying,
delivering cargo to the ISS, with both sections returning to
Earth for reuse. But the Interplanetary Transport System
(ITS) is much more ambitious. Whereas Falcon 9 uses nine
Merlin rocket engines, the ITS will use 42 Raptor engines –
the same size but with almost three times the thrust. TheseThe orbits of Mars and Earth line up for an effective mission
every 26 months, and Musk hopes to use them all from now
on, starting with unmanned tests in 2018 and sending the first
people to Mars in 2026. Funding might come from
governments, private enterprise and even crowdfunding.
Then, far, far in the future, once there are first bases, then
colonies, on Mars, comes the challenge of terraforming –
making Mars like Earth. That might involve first boosting
atmospheric pressure by melting polar carbon dioxide
with nuclear power or solar reflectors, and adding to it
with imported comets and asteroids. That would also raise
temperatures and allow the return of liquid water. But it would
need the protection of an artificial magnetic field. Then algae
or cyanobacteria could start producing oxygen to make the
atmosphere breathable. The stuff of science fiction, yes, but
as we’ve seen, so much of fiction becomes fact.
Turn the page to read Dr Beth Healey’s account of her year
on the Concordia base for the European Space AgencyElon Musk plans to deliver cargo
to Mars in 2018, in preparation
for a human mission in the 2020s
Falcon 9 rocket launch.
Left: Elon Musk (on the
right) hopes to send
private missions to
Mars with his ambitious
SpaceX programmeWords: Martin Redfern. Photographs: Alamy, Getty Images, iStock, Shutterstock, Science Picture Library