Planetary exploration is expensive – as Curiosity’s $2.5bn robotic landing on Mars on Monday morning certainly shows – but it is not an expensive luxury. The more we learn about the other planets, the better we know this one. A study of Earth without reference to the rest of the solar system would be a bit like the story of the UK without a mention of neighbours across the North Sea or the Channel: pointless and dangerously wrong.
The more useful question is whether Nasa could have spent less, and got more for its buck, and that may be more usefully answered when the great experiment is over. All planetary research involves a gamble in which the risks are proportional to the potential winnings. Engineers and scientists had to devise a way of packing autonomous, powered instruments into the lightest possible vehicle, despatch it on an eight-month, 350m mile journey through unpredictable barrages of scorching radiation, smash it into a turbulent and alien atmosphere at 13,000mph and seven minutes later bring it delicately to touchdown on an unpredictable surface.
The ostensible reason for the Mars Science Laboratory mission is the search for evidence of bygone Martian life. It is also a tentative rehearsal for a long-planned joint US-European smash-and-grab raid on the Red Planet. This requires a delivery system that can touch down on an alien surface, choose some suitable soil, scoop it up and bring it safely back to Earth. And that, in turn, would be in preparation for the most dangerous and difficult mission of all: a human expedition to Mars. Inevitably, some have asked: is it worth it?
The great space adventure began in 1957 as cold war posturing. By 1962, satellite technology driven by government investment had begun to change for ever global communications, terrestrial navigation and our understanding of this planet, its oceans and its atmosphere. Because launch costs are prodigious, scientists and engineers worked to devise ever smaller, more efficient and more sophisticated detectors and computing systems, ever smarter automatons and ever surer ways of protecting astronauts and cosmonauts in the orbiting laboratories that have circled the planet. This in turn has delivered expertise to industry to advance human health, create wealth, fuel the startling speed of technological change – and to present humanity with a dramatic new perspective on its only home.
Market forces now routinely exploit the space around the planet. Only governments and international agencies, however, have the resources to blaze the new trails across the heavens, to quite literally break new ground on distant planets. Curiosity got there, so it now looks like a good bet. And science can begin to collect the winnings.