Published online 28 September 2007 | Nature | doi:10.1038/news070924-13

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Space experiments should be done on the cheap

We rarely learn anything Earth-shaking from space labs, says Philip Ball - which is why inexpensive missions like Foton-M3 are the way to go.

Space experiments have rarely seemed as much fun as they did on the European Space Agency's Foton-M3 mission, which blasted off two weeks ago from Russia for a 12-day spell in low-Earth orbit.

Among the 40 experiments in the 400-kg payload were: a test to see if messages could be delivered to Earth from space by lowering them on a 30-kilometre-long tether (see 'Dropping a line from space'); studies of the inner ears of fish (see 'Fish in space help studies of balance disorders') and the salt balance of gerbils; and an investigation of whether any bacteria or organic matter in space debris could make it intact through the furnace of orbital re-entry, by sticking a chunk of Scottish rock onto the spacecraft's side.

None of these experiments seems likely by itself to lead to any major new discoveries or technological breakthroughs. And none can be considered terribly urgent — the fish study has been on the shelf for years, after the first attempt fell casualty to the ill-fated Columbia space shuttle mission in early 2003.

But it would be churlish to criticize the Foton-M3 mission for the incremental nature of its science. Most scientific research is like that. And the roster of experiments in this case is not only impressively long for such a relatively cheap mission but also appealingly diverse, ranging from microbiology to geoscience to condensed-matter physics.

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ESA - AOES Medialab

What's more, the tether experiment arose from a project called the Young Engineers' Satellite 2 (YES2), involving more than 450 students throughout Europe. While the notion of finding a cheap postal method for the indefensibly expensive white elephant known as the International Space Station is rather hard to swallow (and the experiment didn't work out totally as planned), as a way to enthuse students about space research YES2 can't be faulted.

Some components of the Foton-M3 mission do evoke a degree of dèja-vu — how many earlier space experiments have claimed to be "improving our understanding of protein structure by growing protein crystals in weightlessness", for example, or learning about loss of bone mass in astronauts? But there's bound to be some humdrum stuff in over 40 experiments.

Why are we doing this again?

The success of a highly automated mission like this one surely raises questions about whether there's much point in sending people to space instead of machines. If we can design robotic instruments to look at the growth of bone or tissue cells so that we can predict how astronauts might fare on long-term space missions, can we not design robots to replace those very astronauts?

“Foton-M3 provides a nice illustration of proper cost-benefit thinking. The immediate advances in knowledge are small, but so is the cost.”


A report by the UK Royal Astronomical Society (RAS) Commission of the Scientific Case for Human Space Exploration, published in 2005, argues that manned flights are important. That's in part because humans will, for the foreseeable future, be better than robots at responding to unforeseen circumstances in lunar or planetary exploration. Sure. Yet robotic missions will typically cost just a tenth of the equivalent manned ones — so why not send off a series of robotic missions instead of one human one? It's not as though we're in a desperate hurry. And we can afford to lose robotic missions in more ways than one.

The RAS report also argued that "there are benefits for medical science to be gained from studying the human physiological response to low and zero gravity [and] to the effects of radiation." According to the UK Space Biomedicine Group (UKSBG), whose representation seems to have played a key role in the RAS's position on this issue, studying bone demineralization in micro- and zero gravity "could dramatically improve the understanding and treatment of osteoporosis".

But one experiment on the Foton-M3 mission looked at precisely this question of bone mass loss using bovine bone, while another studied bone-forming and bone-degrading cells cultured in vitro. In other words, one of the main putative health spinoffs of human spaceflight, according to the RAS Commission, is already being studied in cheap unmanned missions.

It is conceivable that we would learn something (the UKSBG didn't specify what) from live humans that we would not from dead cows, or from live mice or human cell cultures. But should that unknown increment weigh heavily on the scales that the RAS were seeking to balance?

It's not amazing, but it's cheap

The fact is that many space experiments gain interest not because of the results in themselves but because of the very fact of their having been obtained in space. Who is going to be grabbed by the headline 'Fish studied in lab'? But 'Fish studied in space' will get plenty of attention. The glamour that seems to attach to space experiments almost invariably distorts the import of what they find, all the more so because they are used as their own justification: "look at what space experiments can tell us about stuff that happens in space!"

So Foton-M3 provides a nice illustration of proper cost-benefit thinking. Sure, the immediate advances in knowledge here are small. But so is the cost.

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The 'panspermia' tests, for example, operated by a team from the University of Aberdeen, will at best provide a useful addition to a wealth of previous studies on space- and impact-resistance of organic matter and living organisms. It's unlikely to tell us anything fundamental that we didn't already know.

So when Foton-M3 plummeted back down to Earth near the Russian/Kazakh border on Wednesday 26 September, it should have blown a big hole in starry-eyed visions of space experimentation. This is how it should really be done: modest but intrinsically interesting investigations, realised at a small cost, and performed by robots.

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