Predictably there has been a flurry of discussion about the science aspect of the science fiction movie The Martian. Andy Weir, author of the book on which the movie is based, stresses this aspect of his story. It concentrates on the survival efforts of an accidentally stranded astronaut in a place where you can’t simply find, but need to make all the basics – not only shelter and food but even water and oxygen.
Some points of difference which have been raised include those by Chris Arridge of Lancaster University who pondered the storm which led to the mission abandonment in the beginning of the film. As the Martian atmosphere is only 1% as dense as Earth’s, Arridge has pointed out most storms on Mars would have the force of a gentle breeze found here on Earth. Further dust on Mars accumulates slowly, maybe 1mm and 10mm in 20 years, making it unlikely recently abandoned equipment would need much digging out1. Also technologies such as the ion propulsion and artificial gravity in the interplanetary ship are fiction, although extrapolated from current experiments.
The movie’s cinema release coincided with NASA’s announcement about the likely presence of flowing water at the surface of Mars. An orbiting imaging spectrometer has identified mineral salts which form in the presence of liquid H2O. These hydrated salts, thought to include percholates such as magnesium perchlorate, magnesium chlorate and sodium perchlorate, are contained in linear surface streaks which grow and shrink with the seasons. This has led to new theories about underground water which at least intermittently wicks up to the surface.
Had the announcement been made earlier, would it have made any difference to the story line in The Martian? The answer is probably not. Arridge is concerned that the water produced by the astronaut using rocket fuel as an ingredient could be toxic to humans due to the potential presence of percholates. Seems then some distilling would be in order for either source, assuming of course you were even able to travel to the native water source.
The announcement does increase the odds of finding life on Mars. Realistically this won’t be the ‘little green men’ variety, but perhaps extremophile descendants of single celled life which developed during an ancient wetter period. Of course the more humans visit the surface to search for such life, the greater the risk of biological contamination which might wipe out any such Martians remaining – a version of ‘War of the Worlds’ played out on Mars instead of Earth which might go wholly unnoticed.
However exploration urges seem to be giving way to colonising instincts. The main character considers the growing of a crop of potatoes enough to establish an earthly presence on Mars, seemingly justifying the title of Martian. Perhaps a term like Marth-ling would be better so we retain the ability to discriminate between native and non-native life. And the suggestion that international maritime law applies on Mars is perhaps the concept presented in the movie which requires the greatest exercise of imagination.