The "Jules Verne" is Europe's first Automated Transfer Vehicle (ATV) to fly to the International Space Station. Read on to find out more about its crucial mission. PRE-LAUNCH ATV - THE FIRSTS The ATV is the first completely automated rendezvous and docking ship to go to the ISS The ATV is the largest and most powerful space tug going to the ISS over its mission life It provides the largest refuelling and waste elimination capability for the space station It is the only vehicle on the current timeline able to de-orbit the ISS when it is retired Built for the European Space Agency (Esa), the ATV is an unmanned, automated spacecraft designed to deliver up to 7.6 tonnes of cargo - air, water, fuel, scientific equipment, food, clothing and even personal items - to the platform. The ATV is part of the barter arrangement Europe has with its international partners on the ISS project. Instead of handing over cash to cover station running costs, Europe will take on the major responsibility of resupplying the platform. With the US space shuttle soon to retire and a replacement some years away, this role will be vital when the crew complement rises to six individuals in 2009. The station will continue to receive deliveries from Russian Progress craft and a future Japanese vehicle called the HTV - but neither have the capacity of the ATV. The ATV will also be used to boost the platform to a higher altitude. This is necessary to overcome the effect of atmospheric drag which gradually pulls the ISS back to Earth. One day, the thrust from an ATV's four main engines may be called on to de-orbit the ISS itself when it has reached the end of its mission. Return LAUNCH An ATV has to be launched on a specially prepared Ariane 5 rocket from the European spaceport at Kourou in French Guiana. The ATV mission profile is completely new for the Ariane 5

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Arianes are more accustomed to launching communications satellites with a mass not exceeding 10 tonnes. These spacecraft are usually placed in Geostationary Transfer Orbits (GTOs) that take them out to 36,000km above the Earth. An ATV at launch is about 20 tonnes and has to be put in a Low Earth Orbit (LEO) at just 260km above the Earth. The Ariane 5-ES uses a re-ignitable upper-stage to circularise this low orbit and put the ATV on the right path to catch and dock with the ISS. The upper-stage completes two re-ignitions; the second - after releasing the ATV - puts itself into a controlled dive over the ocean. Return PHASING The ATV is designed to be launched independently of other spacecraft. This enables mission controllers to work other missions around the ATV, as it can be put into orbit and parked temporarily. While the ATV waits, other vehicles, such as the space shuttle, Soyuz "taxis" or the Progress cargo ships, are able to dock with the ISS. When docking, the ATV will approach the ISS from behind and below. It will then simply wait to be instructed to join with the space station at an opportune moment. Return RENDEZ-VOUS Ground staff and astronauts will monitor the final approach

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The ATV uses a sophisticated navigation system to find its own way to the space station. GPS (Global Positioning System) technology is employed to get to within 300m of the platform. Optical sensors are then used for the final approach. These involve flashing laser light off reflectors already positioned around the docking port on the ISS's Zvezda module. The ATV moves in stages towards the station. At each hold point, ground staff in Toulouse will approve the next phase of the automated approach. An astronaut on the ISS also sits in front of a monitor and panel to oversee the docking. Two important buttons - one yellow, one red - allow the astronaut either to stop the ATV in its tracks or, in an emergency, send it away from the station to a safe parking location. Return ATTACHED TO ISS 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 An ATV will stay at the ISS for about six months. Once docked, the crew of the ISS can walk about the ATV without the need for spacesuits. Inside the ATV, the crew will find, water, oxygen and nitrogen, letters from home and other supplies essential for their mission. Dry cargo is packed in white bags and is carried out. Fuels are piped across to the ISS. Fresh air is simply vented into the platform by turning a valve. As these stores are depleted the ATV will be used to store station waste - up to 6.5 tonnes. Return DEPARTURES AND RE-ENTRY The ATV and the ISS rubbish will be buried at sea When the ATV undocks from the platform, it will take this waste into a controlled re-entry over the Pacific Ocean. The ATV will break up into small fragments. It is currently more cost-effective to use the ATV once, rather than design a spacecraft that can be used several times. Design concepts exist for ATVs that allow for part of the vehicle to survive the fiery re-entry, for heat-resistant capsules to be released on the descent. These could be useful if scientists wanted experimental items from the ISS returned intact. However, at the moment, these concepts are not being taken forward. Return WHAT'S IN A NAME? The French author Jules Verne wrote about fantastic voyages - into space, to the bottom of the sea, and around the world. The ATV could also herald extraordinary voyages for Europe. Although the ATV is not designed to carry astronauts, the fact that people can move around safely inside it demonstrates Europe has many of the necessary skills to implement a manned space transportation system should it decide to. Autonomous navigation and docking will be an essential technology for any mission which attempts to return rock samples from Mars - a stated goal of both Europe and the US. Specimens lifted off the surface of the Red Planet would meet up in orbit with a transfer vehicle that had the necessary power to get them back to Earth. Return Cost: Total bill was 1.3bn euros (at least 4 more ATVs will be built) Total cargo capacity: 7.6 tonnes, but first mission will fly lighter Mass at launch: About 20 tonnes depending on cargo manifest Dimensions: 10.3m long and 4.5m wide - the size of a large bus Solar panels: Once unfolded, the solar wings span 22.3m Engine power: 4x 490-Newton thrusters; and 28x 220N thrusters





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