DON Quixote is about to ride again in the service of mankind. A mission into the solar system, named after the famous fictional adventurer, is to crash a spaceship into an asteroid millions of miles from Earth in a Hollywood-style attempt to prove that such a massive body can be deflected off course.
A destructive asteroid heading for the planet is the alarming subject of at least two recent blockbuster films. But the European Space Agency is now planning a 100m mission to create such a Hollywood plot for real.
Space technology companies are being asked to come up with designs for the two Don Quixote craft by the end of the year. One craft, Sancho, the name of the Spaniard's servant, will be launched first to monitor the arrival of Hidalgo, the aristocratic rank which the Don enjoyed.
Hidalgo will then plough into the surface of the asteroid at a speed of 10km a second. The space agency believes the energy caused by the impact will be enough to change the direction of the 500-metre wide asteroid.
Such an asteroid would wipe out an area the size of a large city if, as scientists predict will happen at some time in the future, it were to hit the Earth.
The British space company, EADS Astrium, based in Hertfordshire, has confirmed it will be bidding for the contract.
Andres Galvez, the head of the ESA's Advance Concepts Team, said:
"Don Quixote is all about preparing for a case in which we really will have to take action. We are trying to find out the simplest way of preventing an asteroid from hitting Earth."
Asteroids of varying sizes have previously hit Earth with devastating consequences but, as the global population has grown, the risk to life has been dramatically increased.
Two recent big-budget American disaster movies, Armageddon, starring Bruce Willis and Ben Affleck, and Deep Impact, with Morgan Freeman playing the US president, have focused on attempts to destroy an approaching asteroid and a comet with nuclear bombs planted by astronauts.
In both films, the heroes succeed in saving the planet, but space scientists hope the Don Quixote unmanned missions will render such derring-do unnecessary.
Two asteroids - known as 2002 AT4 and 1989 ML - have been selected as targets for the mission as they will fly into the zone between Earth and Mars, 43 million miles away, after Don Quixote is launched in 2011.
Neither threatens Earth on their current trajectories and mission managers believe that altering their course will present no danger.
Sancho will be sent out first on a journey of at least six months to rendezvous with one of the rocks. It will then go into orbit and deploy probes to examine the asteroid's structure before its sister craft's more dramatic arrival.
Hidalgo will then hurtle in at high-speed and crash straight into the asteroid surface at a predetermined spot. Galvez said: "The thinking is that the spacecraft will form a crater from which considerable quantities of rocky material will be flung out. As a result, the trajectory of the asteroid will be altered.
"We believe this size of spacecraft will result in a deviation of a few hundred metres to a kilometre, which given the distances involved over many years will be enough to knock an asteroid off course from the Earth."
After the explosion, Sancho, which will have retired to a safe distance, will move in closer again. Its role will be to study changes in the asteroid's orbit, rotation and structure caused by Hidalgo's impact.
"This is a hugely exciting mission that is now way beyond paper exercises," said Professor Colin McInnes, head of the department of mechanical engineering at the University of Strathclyde.
"The idea is to use the huge energy produced by the impact to blast enough material off to give the asteroid a push. This is entirely feasible as the kick the asteroid will get is tiny, but if delivered far enough in advance, will make a big difference to its trajectory many years later."
EADS Astrium, the pioneering company which last year launched Inmarsat, the largest commercial satellite ever put into space, plans to produce spacecraft designs by the end of December. ESA experts will then study all the designs put forward and select two. The winner will be chosen in 2007.
EADS Astrium spokesman Jeremy Close said: "We are going to be heavily involved in the bidding as we want to bring our formidable expertise to the project. It's essential that we know more about the composition of asteroids and whether we can deflect them off target."
In Armageddon, a team led by Bruce Willis succeeds in splitting an asteroid in two so it misses Earth. In Deep Impact, although a small comet crashes into the Atlantic, swamping New York under a tidal wave, a larger one that threatens global destruction is shattered by a nuclear explosion.
Such a scenario began to emerge Last December, when the eyes of the world were on the tsunami disaster in the Indian Ocean, scientists spotted a 400-metre-long asteroid, MN4, apparently on a direct collision course with the Earth with impact forecast for 2029. Later calculations found MN4 would not be a danger in that year, but on present trajectories, a future collision cannot be ruled out.