It’s getting a bit hot down here; climate change, political conflict and whatnot. Fancy relocating to Mars? It’s only 36 million miles away, about a nine month journey using a minimum energy trajectory. No problem, surely?
Of course, nine months is a long time to be exposed to solar radiation, which can cause damage to the eyes, gastrointestinal system and central nervous system, as well as vastly increasing the risk of cancer. If you survive the trip, atmospheric pressure on the Martian surface is so low that fresh water begins to boil at 10°C. Add to that even more harmful cosmic radiation, strong winds due to the absence of a magnetosphere, and the lack of accessible water, and it’s easy to understand why our dreams of a Martian home are not yet a reality.
Space agencies across the globe are working on these problems, and there are many projects under way which aim to bring us closer to Mars. Physical shields can combat the radiation problem, but this can make crafts so heavy that huge volumes of fuel are required, rendering it even heavier and in need of even more fuel, which makes it even heavier…and so on. This year, NASA’s space shuttle will complete its final journey after almost 20 years of service, and there is currently no replacement. Instead, the manufacture of American crafts capable of reaching the moon and beyond will fall to commercial contractors.
Other Mars based projects include the European Space Agency’s Eurobot, a rover capable of carrying out complex tasks on Mars. Eurobot and machines like it will take care of tasks astronauts cannot or would rather not do, such as transporting heavy tools and equipment. In the Mars 500 experiment in Moscow, five people are spending 520 days inside a flight simulator in order to investigate the psychological and technical challenges of long-term space travel. The participants are currently ‘on their way home’ and scheduled to ‘land’ in November 2011. One day, we will set foot on Mars, even if it takes a little longer than expected. But Martian colonisation is not the only major milestone in space exploration that we have not yet realised.
Many people believe that the existence of extraterrestrial life is a certainty. Estimates of the number of advanced civilisations in our galaxy range from one to over a million, based on a mathematical formula called the Drake Equation. There is an apparent contradiction between optimistic estimates of the equation and the lack of evidence or contact with such civilisations. This is known as the Fermi Paradox; if there are a million alien civilisations out here, where is everybody?
Frank Drake is the mathematician behind the Drake Equation and founder of the SETI Institute Search for Extra-Terrestrial Intelligence). SETI searches for signals from advanced technological civiisations within our galaxy, looks for earth-like planets outside our solar system, and assesses what it calls the habitability’ of the galaxy for organisms ranging from bacteria to complex life forms. How many advanced echnological civilisations has SETI listened in on since it began operations in 1985? Zero.
One day, SETI might hear something other than a dial tone from space, and perhaps future generations will have the chance to build their lives on he surface of Mars. But in the meantime we just have to carry on working hard, stay patient and above all, keep looking up.