杏吧原创

Destination Mars

IT鈥橲 easy to believe I鈥檓 about to land on another planet. As our
propeller-driven Twin Otter breaks through the cloud, the first thing we see is
the base camp, a hamlet of 20 or so bright yellow and orange tents clinging like
barnacles to the barren Arctic soil. Then someone shouts, 鈥淭here鈥檚 the hab!鈥 and
we all swing our gaze to the other side of the plane. There, on the rim of a
giant impact crater, is a cylindrical white building flying a red, green and
blue tricolour. This is what we鈥檝e all come to see: a simulated Mars base in one
of the most alien environments on Earth.

Two days ago I arrived in Resolute Bay, a one-husky town on Cornwallis Island
in Nunavut, northern Canada. Resolute is just 1500 kilometres from the North
Pole and a short hop from Devon Island鈥66,800 square kilometres of
uninhabited polar desert set in the Arctic Ocean. Every summer researchers come
to Devon Island to study Haughton Crater, a 23-million-year-old impact site in
the centre of the island. And now they are using the place to learn what it鈥檚
like to live on Mars.

Last year members of the privately funded Mars Society built the hab,
officially known as the Mars Arctic Research Station. In July the first wannabe
Mars astronauts moved in. They鈥檝e spent the summer pretending they are on the
Red Planet, wearing Mars suits and exploring the terrain on Mars buggies.
They鈥檒l do the same thing next year and the year after. At the end of it, they
believe they will have laid the foundations for the greatest adventure of all
time鈥攖he human exploration of Mars.

So why practise on Devon Island? Quite simply, the environment and climate
here make it as close as you鈥檒l get to Mars without actually going there. It鈥檚
barren, rocky and permanently cold. The combination of impact crater and polar
desert is common on Mars, though it鈥檚 unique on Earth. The impact rubble is
laced with ground ice, just as it would be on Mars. And at first glance it looks
totally devoid of life.

Haughton Crater was gouged out of the rock 23 million years ago when an
asteroid or comet struck the ground. In seconds the impact drilled a wound 3
kilometres deep and 10 kilometres wide, vaporising a thick layer of limestone
and piledriving into the ancient bedrock beneath. The crater walls then fell
inwards, widening and shallowing the crater in a series of catastrophic
collapses. The explosion probably wiped out every living thing in North
America.

You can still see the debris. The crater rim is studded with razor-sharp
chunks of rock. Just inside the rim are shattercones, fan-shaped scars on the
surface of the rocks where they fractured under the force of the impact. Further
down there are tonnes of rubble that looks like concrete mixed with shards of
granite and glass. This is breccia, formed from the molten and shattered debris
that rained back into the crater after the impact. Normally this stuff is hard
to come by because impact craters erode quickly, but in the high Arctic liquid
water is only around for two months of the year and the breccia is astonishingly
well preserved. You鈥檇 find a similar scene on the heavily cratered surface of
Mars. 鈥淏reccia is typical of Mars, it鈥檚 been blasted so many times,鈥 says
Charles Frankel, a 45-year-old French geologist and science writer who spent a
week in the hab.

鈥淚t鈥檚 very Mars-like here,鈥 says Pascal Lee, the principal investigator on
Devon Island. 鈥淕ranted, the polar desert is not as cold as Mars, not as dry and
probably windier. Gravity and air pressure are different and the UV flux is 8
million times lower. But what we鈥檙e experiencing here is one step closer to
惭补谤蝉.鈥

That鈥檚 what the hab is for. Perched on the western rim of the crater, the
structure is a mock-up of a real Mars landing pod. It鈥檚 the right size and shape
to fit on top of a rocket booster and, apart from the fact that it is built
largely of fibre glass, it鈥檚 the kind of structure the first people on Mars
might call home.

The hab is Lee鈥檚 brainchild. A planetary geologist with the privately funded
SETI institute in Mountain View, California, he has been coming to the crater
and its environs since 1996, trying to read what the rocks can tell us about the
surface of Mars. Four years ago he collared the Mars Society鈥檚 president, Robert
Zubrin, in a parking lot and suggested building a simulated Mars base on Devon
Island. Zubrin has a well-earned reputation as a Mars zealot. The society exists
primarily to lobby the US government to colonise the Red Planet. Its tricolour
flag鈥攖he one flying on the hab鈥攕ymbolises the transformation of Mars
from a lump of dead, red rock to a terraformed Eden of forests and oceans.
Zubrin loved the idea of a dry run on Earth.

For six weeks this summer the hab has housed crews of make-believe astronauts
living and working as if they were on Mars. Under the direction of NASA鈥檚 Ames
Research Center in California, they鈥檝e been planning and executing missions,
dispatching reconnaissance robots, collecting samples and exploring the terrain,
all under pseudo-Mars conditions. Their communications with Ames even have a
six-minute delay built in to simulate the time it would take for radio waves to
cross interplanetary space.

After I pitch my tent, Lee invites me over for a quick look at the hab. I
enter via a hatch at the top of a metal gantry, pass through a cramped wooden
cubicle鈥攖he airlock鈥攁nd into what he calls the 鈥淓VA prep area鈥. EVA
stands for 鈥渆xtra vehicular activity鈥, which is space jargon for going outside.
It鈥檚 basically a dressing room. Hanging there are six mock spacesuits made of
thick white canvas, six helmets and six backpacks, all made by Mars Society
volunteers. 鈥淭hey鈥檙e lo-fi,鈥 Lee admits. 鈥淏ut they鈥檙e quite realistic. They
restrict your senses and they鈥檙e complex to put on. There鈥檚 a checklist. It
takes about half an hour.鈥 We climb a ladder to the upper deck and Lee shows me
the six tiny cubbyholes where the crew sleep, a kitchen, desks and shelves piled
with books. This is where the crew hang out and plan their EVAs. It reminds me
of a student hall of residence. Tour over, I head back to base camp wondering
whether real Mars astronauts would leave their dirty plates in the sink.

Morning arrives squally and overcast, and bleary-eyed people shuffle into the
mess tent for French toast and coffee. It鈥檚 hard to sleep here because it never
gets dark, and last night was worse because of a fierce storm. People crowd
round the stove and discuss their plans for the day. Most of them are biologists
and geologists who spend the summer on Devon Island studying the crater. They
talk of the hab as if it is a sideshow鈥攂ut many of them are spending at
least a week in it, and most of them will come back next year to do it
again.

The researchers depart to their fieldwork, leaving the mess tent to the
media. There鈥檚 me, a couple of other journalists, two photographers and a film
crew from the Discovery Channel. We spend the morning awaiting news from the
hab. Then, about one o鈥檆lock, the radio crackles and the crew announce they鈥檙e
preparing an EVA. We scramble onto all-terrain vehicles (ATVs) and bounce across
a kilometre of rock and mud to the hab.

An hour later we鈥檙e still hanging around outside. The crew are suited and
booted but they鈥檙e not coming out. We can see them through the porthole in the
hatch, standing around in the simulated airlock pretending to acclimatise. It
seems a ridiculous waste of everybody鈥檚 time. The airlock is made of wood, and
anyway they don鈥檛 need to acclimatise. But as Lee later explains, if you want to
learn how to live and work on the surface of another planet you鈥檝e got to
simulate every detail. So every time the crew go outside they dutifully spend
half an hour in the airlock. 鈥淲e don鈥檛 do it to pretend we鈥檙e astronauts,鈥 he
says.

So we play a waiting game. The crew hangs around in the airlock, while we
hover outside in the freezing cold and fiddle with our cameras. Then suddenly
the outer hatch swings open and disgorges an astronaut. It鈥檚 Lee, wearing one of
the mock-up spacesuits. He plods down the steps clad head-to-toe in thick white
canvas, complete with a backpack and goldfish-bowl helmet. Three more suited
figures follow him, walking like cartoon spacemen. I can鈥檛 tell if the suit
restricts their movements or if they鈥檙e doing it for the benefit of the
cameras.

The suit weighs about 7 kilograms, half what a real Mars suit would weigh.
Yet it鈥檚 still a chore to lug around. 鈥淚t鈥檚 a little uncomfortable,鈥 says crew
member Peter Smith, a digital imaging expert from the University of Arizona. He
holds his hand horizontal to chin level. 鈥淚 can鈥檛 see below here,鈥 he says, 鈥渁nd
I can鈥檛 lift my arms above here.鈥 He adopts a Frankenstein鈥檚 monster posture.
Rivulets of condensation run down the inside of his visor.

The four astronauts clamber onto ATVs then trundle off in a stately convoy
along the lip of the crater. We follow them like interplanetary paparazzi, long
lenses and video cameras ready. This exercise is to assess how robots might help
Mars explorers. Yesterday two of them took a robot out to a site a couple of
kilometres from the hab to reconnoitre an interesting feature. Today鈥檚 team will
try to locate the same feature from pictures and GPS readings the robot sent
back. If they find it, they鈥檒l survey the site to see how well the robot
performed.

Forty minutes later we鈥檙e in a valley about 3 kilometres from the hab,
watching Lee hack lumps off a huge brown boulder. This is the feature the robot
identified and Lee seems intent on taking most of it home to prove they found
it. The crew bag up some samples and walk round the boulder. They spot a big mat
of bright orange lichen close to eye level. They seem surprised. The robot
didn鈥檛 notice this.

All the while the film crew are shooting. When they don鈥檛 get what they need
they ask the astronauts to do it again. Lee and his crew grudgingly comply. The
producer shouts 鈥渁ction鈥 and 鈥渃ut鈥 and the day takes on the atmosphere of a
B-movie shoot. To pass the time, the rest of us take turns with my Mars
glasses鈥攁 pair of red-tinted shades that make the polar desert look like
Sojourner鈥檚 famous pictures鈥攁nd wonder out loud whether this is science or
acting.

I sidle up behind the film crew and record a snatch of the astronauts鈥
conversation. 鈥淭here鈥檚 a sense of isolation here, it鈥檚 beautiful. Chksss.鈥 鈥淚
know. You get the sense no human foot ever set here before. Chksss.鈥 鈥淭here鈥檚
just the four of us alone on this planet. It鈥檚 breathtaking. Chksss鈥. The film
crew are lapping it up.

Later on, back in the hab, Lee explains that the media circus is a necessary
evil. This isn鈥檛 just about research, he says, it鈥檚 a lobbying exercise. 鈥淩ight
now, NASA isn鈥檛 going to Mars. They don鈥檛 have permission from Congress.鈥 As far
as he鈥檚 concerned that鈥檚 wrong, and he鈥檚 going to use whatever means necessary
to tell them so. He argues that sending people to Mars would be in the national
interest, in the same way that the Apollo Moon missions were. It would keep the
US at the forefront of technology and safeguard science, engineering and
manufacturing jobs. 鈥淣ow the drawing board is empty, what鈥檚 the next step to
keep the US at the cutting edge?鈥 he asks. If getting the right answer means
posing for the cameras in a canvas spacesuit, so be it.

What he doesn鈥檛 say is that the Discovery Channel has ploughed a lot of money
into this project in return for exclusive filming rights. Without that there
would be no hab, no suits, no Mars-on-Earth.

You can bet it wouldn鈥檛 be like this if NASA were in charge. But at the
moment the agency is a peripheral player. It funds the biology and the geology
but has to distance itself from the hab and the Mars exploration research.
Politically, it can鈥檛 be seen to support a crewed mission. 鈥淣ASA would love this
to happen,鈥 claims Carol Stoker, a roboticist at Ames who鈥檚 spending a week in
the hab, 鈥渂ut they haven鈥檛 got permission from Congress. They actively support
it but they get roasted for it.鈥

It鈥檚 a delicate position. The day I leave, a working prototype Mars suit is
due to arrive at the crater. But only the top half. The trousers have been left
behind, at NASA鈥檚 request. The suit is owned by private company Hamilton
Sundstrand, which makes shuttle suits for NASA and wants to be ready if a real
Mars mission gets the go-ahead. But an internal NASA team is also developing an
鈥渁ll-purpose planetary exploration suit鈥 and doesn鈥檛 want Hamilton to get too
far ahead. So a compromise was struck and the trousers stayed at home.

Have the team really learned anything? 鈥淲e鈥檙e relearning the basics of
working on another planet,鈥 says Frankel. He鈥檚 talking about the simplest
logistics: which tasks become difficult when wearing a spacesuit; how to plan
EVAs with limited oxygen supplies; and dealing with emergencies. 鈥淲e knew it for
Apollo but we鈥檝e forgotten it. We鈥檙e reinventing the wheel.鈥

Others think they鈥檝e got further. Charles Cockell, an astrobiologist with the
British Antarctic Survey, says they鈥檝e learned skills essential to any human
mission to Mars鈥攈ow and where to spot signs of life. Crack open a piece of
breccia and you鈥檒l see greeny-blue streaks running through it like veins in
Stilton. These are colonies of a cyanobacterium, Chroococcidiopsis,
nestling in minuscule fissures created by the repeated freezing and thawing of
ground ice. Without the shelter these fissures offer, the bacteria would dry out
and die. This could be the kind of marginal environment that supports life in
the breccia of Mars.

As far as Cockell is concerned that鈥檚 a good argument for sending humans to
Mars. Robots, he says, aren鈥檛 versatile enough to find out for sure whether
there has ever been life on Mars. Even if we find no sign of life it would still
be interesting, Cockell says. 鈥淚t tells you there鈥檚 no independent origin of
life and no transfer of life from Earth to Mars. It tells you the conditions for
the evolution of life are very special.鈥

As we motor back towards the hab I realise that this is as close as I鈥檒l ever
get to driving across the face of another planet. But some people here have set
their sights higher. 鈥淚鈥檇 go to Mars in a breath,鈥 says Jaret Matthews, a
21-year-old aeronautical engineering student from Purdue University, Indiana.
It鈥檚 a sentiment you hear repeated all over camp. They really want to go to
Mars, and they genuinely believe that there will be a crewed mission one day.
鈥淲e鈥檙e gonna go,鈥 says John Blitch, a special forces officer with the Defense
Advanced Research Projects Agency, who is here to test some robotics. 鈥淚t鈥檚 just
a matter of time.鈥

Back in the mess tent, Cockell jokes that they will all still be coming here
in 50 years鈥 time with their wheelchairs and Zimmer frames. 鈥淲hat we鈥檙e doing is
making preparations for a manned mission to Mars,鈥 he says in a comedy old
fella鈥檚 voice. Everybody falls about laughing.

Simulated Mars base on Devon Island, Canada

Once upon a time there were high hopes. In July 1989, George Bush marked the
20th anniversary of the Apollo landing by announcing that the US intended to
send astronauts to Mars. That November, NASA published a report setting out how
to make it happen. For a few months it looked as though there could be a human
on Mars as early as 2011.

But then NASA started totting up the cost. Sending people to Mars would cost
$500 billion. In October 1990, Congress refused NASA鈥檚 Mars-mission
budget request and from that moment on the ride was as good as over. Six years
later the Clinton administration formally abandoned the plan.

Mars Society president Robert Zubrin thinks NASA got its sums wrong. By using
existing technologies, utilising resources found on Mars and sending four people
instead of six, he reckons the costs could be pared down to as little as
$20 billion. This 鈥淢ars direct鈥 plan is at the centre of the Mars
Society鈥檚 lobbying effort. Sadly for Zubrin and his acolytes, it doesn鈥檛 seem to
be cutting much ice. In February this year, NASA headquarters issued an order to
eliminate all development projects supporting human Mars exploration. The
reason? Budgetary overruns on the International Space Station.

Will we ever go to Mars?

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