Friday, July 13, 2007

'Jules Vernes' set for sea voyage


By Jonathan Amos
Science reporter, BBC News

A segment of the ship prepares to leave Estec on Friday


The Jules Vernes cargo ship has been packed up ready for despatch to the European spaceport in French Guiana.

The vehicle - the biggest, most complex spacecraft ever built in Europe - will launch in January with up to 7.5 tonnes of supplies for the space station.

The ship has been under test for three years at the European Space Agency's technical centre in the Netherlands.

Late on Friday it began the transfer by road and canal to Rotterdam, from where it will go by sea to South America.

The Jules Vernes - or Automated Transfer Vehicle (ATV) to give it its generic name - has been split into three parts and put in containers for the journey.

The ATV is a premiere in many respects
Daniel Sacotte, Esa
The craft heads to the Kourou spaceport as part of a 400-tonne, 50-case shipment that incorporates all the associated parts, apparatus and tools needed to reassemble it and check it prior to launch.

"One of the major issues has been getting the customs paperwork in order," explained Stefan Brosze, ATV transportation manager. "There are members of our team who know exactly where to find everything, right down to the very smallest items."

Test programme

The Jules Verne is the first of at least five ATVs that will fly to the International Space Station (ISS) over the coming years.

Developed at a cost of 1.3bn euros (£0.9bn), the ship incorporates sophisticated automated rendezvous and docking systems. Once launched on an Ariane 5 rocket, the craft can find its own way to the ISS, to deliver air, water, fuel, scientific equipment, food, clothing and even personal items to the platform.

It will also reboost the station, which has a tendency to drift back to Earth over time.

SPACE STATION CARGO TRUCKS
Comparison of ATV and Progress
ATV (left) will resupply the ISS with up to 7,500kg of cargo
Capacity is three times that of the Russian Progress craft (right)
Deliveries will include science equipment, food and clothing
Large tanks can transport vital air, water and fuel supplies
ATV project's estimated cost is about 1.3bn euros (£0.9bn)
At least four craft will follow the maiden ATV - Jules Verne
Named after the author who wrote about fantastic journeys

Esa's research and technology centre, Estec, in Noordwijk has put the space ship through an exhaustive series of tests.

The ATV was placed in an acoustic chamber and blasted with sound to ensure it could withstand the noise and vibration of launch; and in a giant vacuum chamber to see that components would function properly in the extreme conditions of the space environment.

The Jules Vernes was also checked to make sure it met rigorous electromagnetic interference standards; its electronic systems cannot be allowed to interfere with those of its rocket launcher or the space station.

"This is like if you had an old car with the radio on and then you switched the windscreen wipers on, you used to get noise on the radio," explained John Ellwood Esa's ATV Project Manager. "We cannot let that happen with the ATV."

The Jules Verne is scheduled to set sail from Rotterdam on Tuesday onboard the French cargo ship MN Toucan. It will take about 11 days to cross the Atlantic Ocean.

Once in Kourou, an 18-week launch preparation campaign will begin. The ATV will be put back together, fuelled and loaded with its dry and wet cargoes. Finally, it will be placed atop its Ariane 5-ES launcher.

"We could be ready to go in December but we still have many complicated things to do and we need some margin to take into account unforeseen items; but we'll definitely be ready to launch in early 2008," Mr Ellwood said.

Future craft

Europe has a lot riding on the ATV. Its advanced systems will be incorporated into other missions, possibly even a new manned capsule that could take astronauts to the Moon.

The potential for such a vehicle is currently being investigated by Russian and European industrialists.

"The ATV is a premiere in many respects," commented Daniel Sacotte, Esa's director of Human Spaceflight, Microgravity and Exploration.

"We have developed a lot of new technologies for the ATV and these will allow us to do many other things in future in the field of space exploration.

"Also, it helps us fulfil our obligations to our space station partners in terms of cost," he told BBC News.

The latter point refers to the fact that the ATVs are a payment in kind to the $100bn ISS project. Instead of having to pay cash to cover station running costs, Europe has bartered for itself the important re-supply responsibility for the orbiting platform.

The Jules Vernes will have a launch mass of nearly 20 tonnes. Its great bulk means its launcher will have to be specially modified for the task.

Mission planners will use a scheduled Ariane flight in September of unrelated commercial satellites to test the upper-stage manoeuvres needed to put the cargo ship on the right course to the space station.

Graphic: ATV size comparison
ATV capacities: Maximum total load is 7,667kg
1,500-5,500kg - dry cargo; 0-100kg - air (oxygen/nitrogen)
0-840kg - drinking water; 0-860kg - refuelling propellant

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