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Independent  article

A blur of speeding metal, then a cloud of dust as space mission plummets to Earth

By Charles Arthur and Steve Connor

09 September 2004

 

This is the moment that the painstaking research from a three-year, $250m (140m) mission in space crashed headlong to Earth.

The cargo - weighing only as much as a few grains of salt but potentially revealing the origins of our Sun and solar system - screamed past the team of Hollywood stuntmen who had been training for weeks to snare the capsule.

In practice, it had worked perfectly - a mile above the Utah desert the helicopter pilots - fresh from filming Batman 4 - would close in on a slowly descending spacecraft suspended beneath its two parachutes, avoid snagging their rotors, catch it and return the package gently to Earth.

 

Yesterday, at 5pm BST they tried it for real - and the Genesis spacecraft plummeted straight past the pilots and slammed into the Earth at 150mph after both its main and drogue parachutes did not open.

In the blink of an eye, one billion billion particles collected from the "solar wind" turned into a few flecks amid the twisted wreckage of what had been a piece of high-precision engineering.

Watching aghast as the events were broadcast over the web was Dr Ian Franchi, of the Open University's planetary sciences group - which, only a few months before, mourned the loss of the Beagle 2 spacecraft over Mars. He had been hoping to be one of the first in the world to analyse the samples; a whole building had been designed around the need for an ultra-sterile place in which to examine the precious atoms plucked from the cosmos.

 

"The samples are still in there, they are on the ground," said Dr Franchi, as he watched mission scientists race to the crash scene. "That's the good news ... There is a possibility they will be contaminated. It means we will have to be a bit more clever when we come to analyse them. It's not built to withstand such an impact," he said, with huge understatement.

Now, the scientists are wondering whether any data can be retrieved from what is left. Even moving the wreckage is not a trivial task: the explosive charges that should have opened the parachutes apparently failed to go off on re-entry, meaning they could still be live.

Genesis is the first extraplanetary sample return in more than 30 years - the previous being those brought back from the Moon landings. A refrigerator-sized capsule launched in 2001, it had just completed three circuits of the Sun. During those, it opened an aperture allowing atoms and ions thrown off from the Sun at speeds of between 400 and 500 km per second (900,000 mph) to slam into an array of millimetre-thick panels made of gold, silver, sapphire and silicon. Then it closed, and the spacecraft came back to Earth. Too quickly, as it happened.

 

Before the accident, the plan was to remove the panels in an ultra-sterile environment, and study the chemical composition - the "isotopes" - of the atoms there. Because the solar wind particles have such energy, they would be embedded a few nanometres deep inside; by scraping off the top layer with its earthbound contaminants, scientists would have a "time machine", telling them the chemical composition of the solar system as it was six billion years ago when the Sun first began to shine.

Now, nobody is sure whether there will be anything worth examining, or whether the damage will have ruined the panels.

The possibility of a crash was known to the scientists - who have become inured to losing years of work, including the destruction of the Ariane 5 rocket in 1996 soon after lift-off, and the loss of the Beagle 2 spacecraft last Christmas, last heard of somewhere near Mars.

The objectives of Genesis were no less than to peer into the very beginning of the solar system six billion years ago. But scientists have been left now peering into a large hole.

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