Mars rover landing, search for life - experts
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.
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.
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?"
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
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