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4 | NewScientist | 12 June 2010 JOHN RAOUX/AP/PRESS ASSOCIATION IMAGES IF THE TV show Big Brother is anything to go by, the Mars500 mission will have its share of trials and arguments. But does getting six men to spend 520 days locked inside a “Martian spacecraft” that never actually leaves Moscow hold benefits for science? The European Space Agency, which closed the facility’s hatch on 3 June, describes the project as an “extreme test of human endurance”. As the occupants perform the technical feats required for a real journey, their group dynamics, stress levels, immune responses and sleep patterns will be monitored. In a pilot 105-day mission, crew struggled with boredom and a cramped environment. The longer Mars500 should be a better guide to the problems that may arise on a real, 900-day Mars mission. The project has its limitations, Martian Big Brother though. There will be no exposure to radiation or zero gravity, and the psychological conditions will be different, as volunteers know that in an emergency, they can escape. Peter Suedfeld of the University of British Columbia in Vancouver, Canada, suggests that a better way to identify potential stresses might be to use the diaries of explorers on long sea and land expeditions (Planetary and Space Science, DOI: 10.1016/j.pss.2009.05.010). Many people may be banking on high stress levels in Mars500, though: bookies are offering odds on the first person to quit. ‘Torture’ research DOCTORS in the US have taken part in alleged torture experiments on detainees suspected of having links to terrorist organisations, claim human rights activists. The alleged CIA experiments relate to sleep deprivation, interrogation techniques and waterboarding – the practice of simulating drowning by pouring water over a person’s face. Researchers at Physicians For Human Rights (PHR), based in Cambridge, Massachusetts, say they have found evidence of the experiments in declassified documents. The waterboarding experiments supposedly showed that using salty water would make coma less likely. Steven Reissner, PHR’s adviser on ethics, says the CIA’s experiments breach international codes of research, because these demand that subjects give informed consent and that harm to subjects should be minimised. “Both of these were egregiously violated,” he says. The CIA has denied that such experiments were conducted. Ejection pod, please NINE minutes into its maiden voyage, the privately owned Falcon 9 rocket was in orbit, scoring major points for the idea of commercial space taxis. But a crucial safety hurdle still looms. The company SpaceX of Hawthorne, California, wants to use its rocket to fly NASA astronauts to the International Space Station after the remaining space shuttles retire at the end of 2010. The success of Falcon 9’s –Short cut to a global census– –Space taxi in waiting– Species count slashed TALK about overestimation. Only 5.5 million species share our planet, a much smaller number than the older, often-quoted estimate of more than 30 million. Most vertebrates and plants and many microorganisms have been documented. Much of the uncertainty in such global estimates lies with arthropods, a phylum that includes insects and spiders. The global figure of over 30 million species was suggested in 1982 by Terry Erwin at the Smithsonian Institution in Washington DC. He counted the species of beetle exclusive to one tropical tree species in Panama, then multiplied by the number of tree species globally. He also scaled up the result to take into account the fact that beetles make up around 40 per cent of arthropod species. Now Andrew Hamilton of the University of Melbourne, Australia, has revised the estimate using observations of beetle species on 56 tree species in Papua New Guinea. He concludes that there are between 2.5 and 3.7 million arthropod species, and that the total number of species on Earth is around 5.5 million (The American Naturalist, DOI: 10.1086/652998). Neither he nor Erwin included bacteria, however, as they are hard to separate into species. There are always limitations in using data from one country, says Corey Bradshaw at the University of Adelaide, Australia. Still, Hamilton’s estimate is “perfectly reasonable”, says Margie Mayfield of the University of Queensland, Australia. “Six volunteers will spend 520 days locked inside a ‘Martian spacecraft’ that never leaves the ground” MARK MOFFETT/MINDEN/FLPA UPFRONT
