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Jules Verne Demonstrates Key Capabilities to Navigate Safely Behind the ISS Using Relative GPS Navigation

Jules Verne ATV today demonstrated its ability to navigate safely from a point 39 km behind the ISS to a stand-off point just 3.5 km away using relative GPS navigation. The vessel then executed an Escape manoeuvre commanded from the ATV Control Centre in which the craft flew off to a safe distance.

“All systems were completely nominal, which is very satisfying for this first day of really testing the rendezvous capability of the spacecraft,” said John Ellwood, ESA ATV Project Manager.

Today’s demonstration also confirmed Jules Verne is able to establish a continuous two-way data link with the ISS. Using the high-rate S-band communication link, which was switched on at a distance of 40 km from the ISS, Jules Verne for the first time conducted relative GPS (Global Positioning Satellite) measurements with the Station. Relative GPS is a navigation technique executed by computers between the ATV's GPS receiver and the ISS GPS receiver that enables ATV to navigate relative to the Station with very high accuracy.

For both the flight control team in Toulouse and the ISS flight crew, this 64 kilobits/sec transmission rate also made it possible to test all the crucial data and communication connections between the two spacecraft, including some monitoring capability on both sides to send and receive communications.

When Jules Verne reached the closest holding position, at 3.5 km from the ISS, the bus-sized spaceship turned on its external tracking lights and activated the Russian-built Kurs rendezvous radar with equipment on both spacecraft. The robust and historical Kurs system, a concept which has been used for decades, provides relative distance and velocity with independent data for the crew monitoring during Jules Verne's final approach to the Station.

During the demonstration the astronauts on board ISS reported they were able to see Jules Verne with the naked eye. The spacecraft could also be seen via screens inside the ATV Control Centre. “For the flight control team the sight of the ATV thrusters firing was particularly exciting and brought the whole thing to life,” said Bob Chesson, Head of ESA’s human spaceflight operations. “It was fantastic to be reunited with Jules Verne and to see it performing so perfectly which is very promising for the days to come.”
Data collected throughout the first demonstration day will now be analysed by the ESA JADOR (Jules Verne ATV Demonstration Objectives Report) team. A report will be submitted to the ISS Mission Management Team. After an assessment and authorisation on 30 March, ATV can proceed to Demonstration Day 2 on Monday (including an approach to within 11 m of the ISS).

“The first analysis from the JADOR are looking pretty good. We are going to spend some hours now analysing them further. We are quite confident,” said Alberto Novelli, ESA’s Mission Director at ATV-CC.

Note for International Space Station
The International Space Station (ISS) is a research facility currently being assembled in space. The on-orbit assembly of ISS began in 1998. The space station is in a low Earth orbit and can be seen from Earth with the naked eye: it has an altitude of 350-460 km (217-286 statute miles) above the surface of the Earth, and travels at an average speed of 27,700 km (17,210 statute miles) per hour, completing 15.77 orbits per day. The ISS is a joint project among the space agencies of the United States (NASA), Russia (RKA), Japan (JAXA), Canada (CSA) and eleven European countries (ESA).

The Brazilian Space Agency (AEB, Brazil) participates through a separate contract with NASA. The Italian Space Agency similarly has separate contracts for various activities not done in the framework of ESA's ISS works (where Italy also fully participates). China has reportedly expressed interest in the project, especially if it is able to work with the RKA. The Chinese are currently not involved, however.

The ISS is a continuation of what began as the U.S. Space Station Freedom, the funding for which was cut back severely. It represents a merger of Freedom with several other previously planned space stations: Russia's Mir 2, the European Columbus and Kibo, the Japanese Experiment Module. The projected completion date is 2010, with the station remaining in operation until around 2016. As of 2008, the ISS is already larger than any previous space station.

The ISS has been continuously inhabited since the first resident crew entered the station on November 2, 2000, thereby providing a permanent human presence in space. The crew of Expedition 16 are currently aboard. At present the station has a capacity for a crew of three. In order to fulfill an active research program it will be necessary to eventually hold 6 crew members. Early crew members all came from the Russian and U.S. space programs. German ESA astronaut Thomas Reiter joined the Expedition 13 crew in July 2006, becoming the first crew member from another space agency. The station has, however, been visited by astronauts from 15 countries. The ISS was also the destination of the first five space tourists.

The station is serviced primarily by Russian Soyuz and Progress spacecraft and by U.S. Space Shuttle orbiters. On March 9, 2008, the European Space Agency ESA launched an Ariane 5 with the first Jules Verne ATV Automated Transfer Vehicle toward the ISS carrying over 8,000 kilograms of cargo. Rendezvous and docking are planned for early April, 2008.

The assembly of the International Space Station is a major aerospace engineering endeavor. When assembly is complete the ISS will have a pressurized volume of approximately 1,000 cubic meters. Assembly began in November 1998 with the launch of Zarya -- the first ISS module -- on a Proton rocket, and as of March 2008 assembly is about 70% complete.

Two weeks after Zarya was launched, the STS-88 shuttle mission followed, bringing Unity, the first of three node modules, and connecting it to Zarya. This bare 2-module core of the ISS remained unmanned for the next one and a half years, until in July 2000 the Russian module Zvezda was added, allowing a maximum crew of three astronauts or cosmonauts to be on the ISS permanently.

Note for Automated Transfer Vehicle
An Automated Transfer Vehicle or ATV is an expendable, unmanned resupply spacecraft developed by the European Space Agency (ESA). ATVs are designed to supply the International Space Station (ISS) with propellant, water, air, payload and experiments. In addition, ATVs can re-boost the station into a higher orbit.

The ATV is designed to complement the Progress spacecraft, having three times its capacity. Like the Progress, it carries both bulk liquids and relatively fragile freight which is stored in a cargo hold kept in a pressurized shirt sleeve environment so that astronauts can have access to it without putting on a spacesuit. The ATV pressurized cargo section is based on the Italian-built Multi-Purpose Logistics Module (MPLM), which is already in service as a Shuttle-carried ‘space barge’ transporting equipment to and from the Station.

ATV incorporates a Russian-built automatic docking system, similar to those used on Soyuz manned ferries and on the Progress re-supply ship. Also like the Progress, the ATV will additionally serve as a container for the station's waste.

Each ATV weighs 20.7 tonnes at launch and has a cargo capacity of 8 tonnes:
1,500 kilograms (3,300 lb) to 5,500 kilograms (12,000 lb) of dry cargo (re-supply goods, scientific payload, etc.),
Up to 840 kilograms (1,900 lb) of water,
Up to 100 kilograms (220 lb) of gas (nitrogen, oxygen, air), with up to two gases per flight,
Up to 4,700 kilograms (10,000 lb) of propellant for the re-boost maneuver and refueling the station. The ATV propellant used for re-boost (monomethylhydrazine fuel and N2O4 oxidizer) is of a different type from the payload Russian refueling propellant (UDMH fuel and N2O4 oxidizer).

The prime contractor for the ATV is EADS Astrium Space Transportation, leading a consortium of many sub-contractors. The prime contractor office is currently located in Les Mureaux, France, and will be transferred to Bremen, Germany, once the development is completed and the production of the four initial units starts. In order to facilitate the relationship between the contractor and ESA, an integrated ESA team at the Les Mureaux site has been established for the duration of the development.

The first ATV arrived at the ESA spaceport in Kourou, French Guiana on 31 July 2007 after a nearly two week journey from Rotterdam harbour and was launched on March 9, 2008. The Jules Verne was the first ATV to be launched. Astrium Space Transportation builds the ATVs in its facility in Bremen. Contracts and accords were signed in 2004 for four more ATVs, which should be launched about once every two years, bringing the total order, including Jules-Verne, to five.

To this end, RSC Energia has signed a 40 million euro contract with one of the main subcontractors of EADS Astrium Space Transportation, the Italian company Thales Alenia Space, to supply the Russian Docking System, refuelling system, and Russian Equipment Control System. Within the EADS Astrium Space Transportation led project, Thales Alenia Space is in charge of the pressurized cargo carrier of the ATV. These pressurized cargo carriers are produced in Turin, Italy.

Pictures Overview
In figure 1, Artist's impression of ESA's ATV

In figure 2, The Escape command was sent from the ATV Control Centre

In figure 3, ATV approached to within 3.5 km