Probes are being dispatched to explore the solar system, but will people follow them?by Martin Rees / April 20, 2011 / Leave a comment
On 17th March, Nasa’s Messenger space probe was injected into orbit around Mercury; it is now beaming back data from only 200km above the planet’s parched and cratered surface. The probe, which has already tripled the number of images of Mercury available, aims to solve questions such as whether water ice lurks at the shadowy poles of Earth’s smallest cousin.
Messenger is the most recent in a series of unmanned spacecraft launched to explore planets, moons, comets and asteroids. In the coming decades, huge numbers of miniaturised probes could be dispersed to explore the solar system more fully.
But will people follow? It’s 50 years since the Soviet astronaut Yuri Gagarin’s first flight; Neil Armstrong’s “one small step” came only eight years later. Yet it’s nearly 40 years since the last Apollo astronauts returned from the moon; today’s astronauts go no further than the International Space Station (ISS). At a cost of around $100bn, the ISS is the most expensive artefact ever constructed, but it is neither useful nor inspirational.
The US’s firm plans don’t even include further moon landings. Instead, Nasa envisages a less demanding but still progressive programme: an expedition to an asteroid, a number of lunar orbiters, and eventually a trip to Mars and back (perhaps alighting briefly on one of its small moons, Phobos or Deimos). The latter would be far easier than landing people, along with all the equipment needed for their return trip, on the red planet itself.
Nasa is too constrained by public and political opinion to be anything but risk-averse. In 130 attempts, only two shuttle flights have failed—a level of risk that astronauts or test pilots would willingly accept. But the shuttle has been promoted as a vehicle safe enough for civilians, and each failure has caused a degree of national trauma. The disintegration of the Space Shuttle Challenger in 1986, resulting in the deaths of its crew, was followed by an investigation and a 32-month hiatus in Nasa’s space programme. A similar process followed the 2003 Columbia shuttle disaster.
Future expeditions to the moon and beyond won’t be politically and financially viable unless they are cut-price ventures, spearheaded by individuals prepared to accept high risks. The US now contracts with private companies to undertake launches, rendering Nasa more like an airport authority than an airline. The Falcon 9 rocket system, developed by the entrepreneur Elon Musk’s company SpaceX, has successfully…