Ideas that could further exploration in space are coming from a surprising source - animals such as ants, fish and squirrels.
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The future of space exploration could lie in biomimetics, where engineering meets biology. In effect, it steals nature's evolutionary tricks to create revolutionary applications.
Engineers like Dr Alex Ellery, head of the Robotics Research Group at the University of Surrey, are trying to find out how natural systems might inspire human-made technology in space.
"One obvious way is in the way nature, in particular plants, package themselves into very small volumes, and yet deploy large structures, like flowers and so on," he told BBC World Service's Discovery programme.
"We can learn about how to package things like spacecraft, and then have them deploy their solar arrays, antennae and so forth.
"The applications are essentially limited only by our own imagination."
One example is the self-organisation of ant colonies. Ants adopt complex tasks without any specific instructions about what to do.
Machines which could act independently and intelligently would be perfectly suited to the hostile environment of space, and could make space exploration safer.
In the future, self-organising systems modelled on ant behaviour could, for example, monitor space shuttles, sensing and repairing damage.
"The only real examples that we have of structures that can monitor themselves, and indeed repair themselves afterwards, are biological structures," said Don Price of Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO).
"It's natural to look to biology to try and understand how these sort of things can work."
Dr Price explained that he has been studying the way ants deal with damage to themselves and their colony.
Working from this, he has devised an array of "damage sensors" which can be fitted around the outside of spacecraft, like skins. Thousands of sensors could pick up the smallest of disturbances.
Each currently can communicate only with the sensors next to it. However, Dr Price is working on a set of algorithms which will allow all the sensors to interact, meaning the system as a whole can act like an ant colony.
Dr Price also explained that to avoid using dangerous spacewalks to repair damage, he was investigating the possibility of having "groups of small robots who can do things co-operatively and indeed can do it just the way swarms of ants can repair things, or defend their nest."
Other creatures are also inspiring designers of unmanned craft.
Biomimeticists are looking at how to incorporate flying and jumping. Among them is Keith Paskins of the University of Bath, who is trying to mimic flying squirrels.
The squirrels have floppy skin attached to their wrists and ankles, which they can stretch out to make a gliding surface. The animals also appear to be able to control their gliding through rapid movements while in the air.
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"If we've got something that could jump, we'd then like it to be able to control itself in the air. But the problem with flying is that it's very high energy," Mr Paskins said.
"Although work has been done with micro-air vehicles, at the end of the day when their batteries run out the thing is dead, and it's very high-energy to keep flapping.
"Gliding is almost free energy. If you can stick out a wing and just glide down, then you can get yourself a lot further for very little economic expense," said Mr Paskins.
His colleague, Dr William Megill, believes using the motion of a Black Ghost Knife fish could make robots that swim, to explore oceans in space, such as on the moons of Jupiter.
"It's about efficiency," he said.
"Space is all about maximum power, maximum strength, for the minimum amount of weight - because everything's got to be rocketed off into space.
"If we can make a propulsion system that is many times more efficient, then we need a smaller motor, and we need less energy in terms of batteries."
Bath's biomimetics professor, Julian Vincent, has mimicked the drilling abilities of a wasp to create a robot much better equipped for taking samples for analysis.
He has taken an electric jigsaw tool and added an extra gearbox at the front and an extra blade at the bottom.
This bio-inspired drill could be useful for gouging deep into rocks, in particular on asteroids where there is little gravity, which would effectively leave normal drills bouncing on the surface.
Space agencies are said to be sceptical about biomimetics
"We worked out how a wood wasp drill works, and then tried to make a machine out of it," he added.
"One side pushes in and cuts, and the other side is pulling itself out and gathering the sawdust and taking it up to the top.
"In a way it is a paradigm of biomimetics. We allowed the wasp to do nearly all our work. Now we have a pretty good prototype first time round, courtesy of nature."
However, Dr Alex Ellery of the University of Surrey said that space agencies themselves are "somewhat sceptical".
"Space engineers are by nature extremely conservative, and they don't like anything new.
"They tend to work on the basis that if something has worked in the past, they want to re-utilise it again."