the moon makes no sense to make a base. Mars is big enough to manipultate the atmosphere to a earth like planet.
Now Nasa looks to change Mars into a garden of Earthly delights
Fiction could become reality as scientists plan to 'terraform' the fourth rock from the Sun
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Robin McKie, science editor
The Guardian, Sunday 28 March 2004
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Finding life on Mars has proved an elusive dream for decades. But scientists now believe they may be able to do it for themselves - by turning the Red Planet into a blue world with streams, green fields and fresh breezes and filling it with Earthly creatures.
The idea - known as terraforming - sounds like science fiction. But turning Mars into an Earthly paradise is being taken seriously by increasing numbers of researchers. They believe that, billions of years after its last seas and rivers dried up, Mars could be restored to its ancient glory thanks to human ingenuity. Its craters would become lakes and its red, parched hillsides would be covered with forests, ultimately providing mankind's teeming ranks with a new home.
This startling concept will be the focus of a major international debate, to be hosted this week by America's space agency, Nasa, which is preparing a multi-billion-dollar Mars research programme at the request of President Bush. Leading researchers as well as science fiction writers, including Arthur C. Clarke and Greg Bear, will attend.
'Terraforming has long been a fictional topic,' said Dr Michael Meyer, Nasa's senior scientist for astrobiology. 'Now, with real scientists exploring the reality, we can ask what are the real possibilities, as well as the potential ramifications, of transforming Mars.'
Most astronomers agree that Mars could be turned into a little Earth, though it would take decades to achieve this goal and would require massive expenditure. But many scientists are horrified by the concept.
'The idea of terraforming Mars is extreme, but it is not cranky - that is the truly horrible thing about it,' said Paul Murdin, of the Institute of Astronomy, Cambridge. 'If it was just a silly science-fiction notion, you could laugh it off. But the idea is terribly real. That is why it is dreadful. We are mucking up this world at an incredible pace at the same time that we are talking about screwing up another planet.'
Over the past months, astronomers have become increasingly confident they will find Martian lifeforms after decades of disappointment. Europe's Mars Express and America's two robot rovers, Spirit and Opportunity - which are all investigating the planet at present - have detected strong evidence that water, mixed with soil, exists in large amounts on Mars.
In addition, two different groups of scientists yesterday revealed they had found traces of methane in the Martian atmosphere. The gas is a waste product of living creatures and could be a byproduct of Martian microbes living in the Red Planet's soil.
It is the risk that terraforming poses to these sorts of organisms that outrages scientists, such as Dr Lisa Pratt, a Nasa astrobiologist based at Indiana University.
'It is very depressing. Before we have even discovered if there is life on Mars - which I am increasingly confident we will find - we are talking about undertaking massive projects that would wipe out all these indigenous lifeforms, all the strange microbes that we hope to find buried in the Martian soil. It is simply ethically wrong.'
To terraform Mars, engineers would have to find a way of thickening its atmosphere, whose pressure is a hundredth of that on Earth. In addition, ways will have to be found to heat up the planet. At present its surface temperature can plunge to minus 60C and below.
However, both goals - heating and thickening - could be achieved together, say researchers. One idea is to build a large mirror, many miles in diameter, and place it orbit above Mars. This would then be used to focus the Sun's rays onto a polar icecap, melting it and releasing its frozen carbon dioxide contents. The carbon dioxide would then trigger greenhouse heating.
The alternative would be to construct plants for generating super-greenhouse gases - made of complex combinations of carbon, chlorine and fluorine, and which are thousands of times more effective than carbon dioxide at trapping heat. These would be built at strategic sites across the planet and should also trigger global temperature rises. Thickening the Martian atmosphere would also protect its surface from the ultra-violet radiation that bombards its surface and which would otherwise kill off most Earth-like lifeforms on the planet.
According to Dr Chris McKay - based at Nasa's Ames Research Centre in California and a participant in this week's terraforming debate - either method could provide the terraforming project with a crucial kick-start. With a thicker, warmer atmosphere, ice trapped in the Martian soil would melt and could be used to sustain agriculture. With plants and trees imported from Earth growing and producing oxygen, the atmosphere would become slowly more Earth-like. 'We should get serious about sending life to Mars,' McKay said.
Other scientists remain cautious. 'We now know Mars used to have an atmosphere, but it disappeared for reasons that are still unclear,' said Monica Grady, a planetary scientist at the Natural History Museum, London. 'If we restore Mars's atmosphere, we could easily find it disappeared again. We would have done some devastating things to the planet for a temporary effect. That is certainly not ethical.'
The point is backed by Pratt. 'If we find life on Mars, the philosophical implications will be profound,' she said. 'If it is unlike Earthly life and has a different genetic code, this will show that living beings evolved separately on two neighbouring worlds. Life is therefore likely to be ubiquitous throughout the galaxy.
'If it has the same genetic code, however, it will indicate that one planet must have contaminated the other - probably by rocks being blasted across the solar system following meteorite impacts. We may really be Martian in origin.
'Given the importance of these issues, we simply cannot risk starting a global experiment that would wipe out the precious sensitive evidence we are seeking,' she added. 'This is just not on.'