Mars rover landing, search for life - experts respond
6 August 2012
NASA's latest Mars rover, Curiosity, is making its final approach to the Red Planet, due to touch down today at 05:31
UTC (17:31 NZT).
Full information on the mission and the rover can be found on the official Mars Science Laboratory website.
The Science Media Centre rounded up comments from New Zealand experts on the upcoming landing and mission (see below), as well as the possibility of life on Mars.
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We asked biologists who study extremophiles -- life forms on Earth that live in incredibly harsh conditions -- what the
Curiosity rover's mission means for them and their science, and how recent discoveries in their field have changed our
ideas about life on other planets.
Professor Craig Cary of Waikato University studies life in extreme environments like the Dry Valleys of Antarctica,
widely considered to have the most Mars-like conditions of any place on Earth. He comments:
"The possibility of finding life is absolutely there. For life, you need water, and you need a source of energy The
problem on Mars is the availability of water.
"All life forms need water, but the question is: at what level? We know there are organisms that can live in ice, for
example, because ice has a tendency to create little channels that remain liquid even though the rest of the ice is
frozen. Antarctic researchers have found bacteria that are hundreds of thousands of years old, dormant but still alive,
in these channels. So if there's permafrost or ice underground, it's a possibility.
"We know there are bacteria that can live in what would appear to us a very dry environment. Certain minerals attract
water in what we call a mono-molecular layer -- just a thin film of water across the surface of the mineral, but that's
enough for them to access. Although it seems like dry rock, for bacteria it can be quite a lush environment.
"The problem with Mars is that it's a big planet. You can't pick a location that you can be absolutely certain is the
right place to go looking -- it's a gamble. There are probably a hundred sites on the planet that would be good sites to
go to.
The first thing to do is get the rover securely on the ground. Then, I think it's going to be very, very exciting over
the next couple months.
"I think we're going to be surprised.
I've dreamed of something like this happening for a long time, hoping it would happen in my lifetime. I'm all for these
exploratory trips.
"Bacteria aren't primitive life forms at all. They're incredibly advanced. Over 3.5 billion years of evolution, they've
acquired the tools to occupy every niche on this planet, under some of the harshest conditions that the planet imposes.
When you think about that adaptive capability, all bets are off. What's on Mars? Anything could be up there."
Dr David Saul is Principal Scientist at ZyGEM, a biotechnology company that specialises in finding applications for
enzymes extracted from extremophiles. He comments:
"When astrobiologists look for life elsewhere in the solar system, many people believe that they are looking for
entirely alien life. It would be great if they found that, but there is a more likely possibility that life on Mars (or
Europa) shares a common origin to life on Earth and that in the early stages of planetary formation, there was cross
contamination between the planets.
"It sounds far fetched suggesting that life could survive the trip through space, but life on Earth has already proven
that microbes can exist in the most remarkable environments. They live in nuclear reactors, in the sands on the
Antarctic McMurdo Dry Valleys, in water above boiling point, and deep in the rocks many kilometres below our feet.
"When you look at these terrestrial species, you realise that the trip between Mars and Earth would have been relatively
straightforward if a meteor flung rocks into space from one planet to the next. More and more, it's looking like there
was never any border security between the planets. Who knows, we may have a Martian ancestry ourselves. Wouldn't it be
nice to discover that the Garden of Eden was in fact a volcanic vent on Mars?"
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Dr Allan McInnes, Senior Lecturer, University of Canterbury School of Electrical and Computer Engineering. Dr McInnes
was a systems engineer working on the Mars rover programme from 2000 - 2003 and worked on the Spirit and Opportunity
rovers. He comments:
Biggest technical differences between Curiosity and previous NASA Mars rovers:
"Curiosity is huge in comparison. Spirit and Opportunity were maybe the size of a golf cart, Curiosity is the size of a
Mini Cooper, weighs 900kg, is twice as long, five times as heavy and produces about three times as much power.
"Because it is so much more massive, they needed to find a different way to land on the surface. They've devised quite a
neat scheme derived from how the old Apollo capsules from the moon programme used to land. It will actively adjust what
its doing while moving through the atmosphere to allow it to compensate for wind gusts.
"Spirit and Opportunity landed on air bags, dropped to the surface and bounced a bit. They couldn't build airbags big
enough to manage that with Curiosity. Instead they fly in and hover above the surface and then drop the rover down on
cables.
"They have to do that instead of landing on the surface because to land on the surface without getting dust all over the
instruments, you'd need a complex, very tall lander and a ramp to get the rover off.
"It's almost like a sky crane helicopter where the lander flies in, drops the rover down, the cables detach and the
landing stage flies away so its not anywhere near the Rover when things get started."
Future possibilities for movement around Mars:
"I've seen conceptual level designs for a unmanned aerial vehicle (UAV) or glider of some kind. A one stage someone was
looking at a blimp or airship.
"Propulsion is also a possibility. If you have rocket propellant you have to cary it all the way from Earth, that's a
lot of mass. There are concepts for so-called in-situ propellant production. You basically create new rocket propellant
on the surface of Mars by processing atmospheric gas or chemicals out of some of the rocks.
"But that introduces the potential for something else to go wrong. If you can't produce fuel, potentially your mission
is over."
What can be learnt about Mars for future manned missions to the Red Planet:
"Curiosity is specifically designed to answer some of the questions that will help with future manned Mars missions. One
of the primary mission goals is to make an extensive study of surface radiation levels and really understand what's
going on there. If you are going to put people on Mars, you want to make sure they will not be exposed to extreme
radiation.
"The geological data it can bring back is going to be extremely helpful. A lot of the plans for human development of
Mars allow for in-situ propellant production. Understanding what chemicals are there to use is beneficial as well as
just a better understanding of the Mars environment for the safety of people involved."
On waiting for touch-down:
"It's incredible nervousness as you wait. In general, working on a programme like that is a huge amount of fun, but its
a lot of work and stress at times, particularly with the Mars programme. You can only send a ship to Mars maybe once
every couple of years. You need to have the alignment between Earth and Mars just right to do it. If you miss that two
year deadline you are in big trouble."
Private sector involvement in space exploration:
"In the longterm, that's how its going to have to happen. That's how we've explored new frontiers, its largely been
private groups that have done it. It's become harder and harder for the US government to justify to taxpayers why you
are doing these things
"There are companies planning to mine asteroids for minerals. Whether they'll look at privately funded missions to Mars
is harder to say. It's not clear what the economic benefits would be. But having private companies involved in things
like launch vehicles has worked well."
Mo
Note to editors
The Science Media Centre (NZ) is an independent source of expert comment and information for journalists covering
science and technology in New Zealand. Our aim is to promote accurate, evidence-based reporting on science and
technology by helping the media work more closely with the scientific community. The SMC (NZ) is an independent centre
established by the Royal Society of New Zealand with funding from the Ministry of Science + Innovation. The views
expressed in this Science Alert are those of the individuals and organisations indicated and do not reflect the views of
the SMC or its employees. F
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