So said British mountaineer George Mallory in 1923, when asked by The New York Times why he wanted to climb Mount Everest. That philosophy could also be said to motivate much scientific endeavour, particularly in pure or theoretical research where applications may not be apparent, where there may be no otherwise tangible benefit to mankind beyond simply knowing.
In that same spirit of endeavour, NASA is planning a manned mission to Mars. Among astronomers and astrophysicists, there is widespread opposition to the programme — you certainly won't have heard it here first. In the face of stringent budget constraints, so much astronomy, planetary science, cosmology and physics research stands to be delayed or sacrificed to finance a project that is championed by administrations — of NASA, and of President George W. Bush.
When John F. Kennedy vowed in 1961 that the United States would put a man on the Moon within the decade, the world was a different place, and not necessarily a better one. After the USSR stole the lead with the launch of the Sputnik satellite and Yuri Gagarin's first spaceflight, cold-war posturing required that the USA respond in kind. Subsequent administrations have attempted to capture some of that spirit of bold endeavour and attention-grabbing triumph: Ronald Reagan's vision for an International Space Station (ISS), still under construction some 20 years later; and now Bush's vision of a man on Mars.
Safe spaceflight is no less of a challenge now than it was in the 1960s. Last month, the eyes of the world were on the space shuttle Discovery, when NASA Administrator Michael Griffin overruled the organization's Chief Safety Officer and Chief Engineer to confirm its launch on 4 July, despite the loss of a patch of insulating foam from the external fuel tank — a similar incident during launch having claimed the shuttle Columbia and its crew three years before. With the safe return of Discovery to Earth two weeks later, Griffin's decision was vindicated. But, as Griffin himself has stressed, shuttle flights are never without risk.
Given that risk, what is the manned space programme achieving? The ISS is fast becoming a white elephant, its science programme desperately eroded. On its latest flight, Discovery delivered astronaut Thomas Reiter to carry out experiments in ESA's Astrolab onboard the space station. Those experiments are nearly all concerned with the physiological implications of extended stays by humans in space — cardiovascular stress, radiation damage to chromosomes, changes in immune response, and other ills. One experiment, according to a rather half-hearted listing on the Astrolab website, will study a microsphere-laden plasma under weightless conditions; physicists will not be awaiting the results with eager anticipation.
This is not to imply that there is no benefit to manned spaceflight — after all, it was Discovery that put the Hubble Space Telescope in orbit, and a shuttle may undertake a further servicing mission to extend the telescope's life. But arguably the best science to come out of space exploration is from unmanned missions. Take last month alone: on the same day as Discovery's launch, and hence going largely unnoticed, ESA's Venus Express moved from its in-orbit commissioning phase to being declared operational, and is already sending back remarkable data on the dynamic atmosphere of our neighbouring planet; a remotely controlled fix brought the Hubble's Advanced Camera for Surveys back online after an electronics glitch; and, in a report made on the basis of the continuing stream of information from orbiting satellites and the hugely successful Mars rovers, a National Academy of Sciences committee advised NASA on the optimization of its plans for further remote exploration beyond 2010.
The example set by the unmanned missions is a good one. “Because it's there” is no reason for man to set foot on Mars.