The European Space Agency’s Johannes Kepler Automated Transfer Vehicle completes its mission successfully, carrying supplies and automatically docking with the ISS.
Eight days after launch, the European Space Agency’s (ESA) latest Automated Transfer Vehicle, Johannes Kepler, completed a flawless rendezvous and docking with the International Space Station (ISS) at 17:08 CET (16:08 GMT) to deliver essential supplies.
The approach and docking were achieved autonomously by its own computers, closely monitored by ESA and the French space agency (CNES) teams at the ATV Control Center in Toulouse, France, as well as the astronauts on the ISS. ATV’s own second set of sensors and computers provided an independent check.
Although both ATV and the ISS orbit at 28 000 km/h, the relative speed during final approach remained below 7 cm/s and the accuracy within a few centimeters. Johannes Kepler closed in on the ISS from behind in order to dock with Russia’s Zvezda module.
At close range, the 20-ton unmanned spaceship computed its position through sensors pointed at laser reflectors on the ISS to determine its distance and orientation relative to its target.
ATV’s docking probe was captured by the docking cone inside Zvezda’s aft end at 16:59 CET (15:59 GMT). The closure of hooks completed the docking sequence some nine minutes later.
“We are more ready than ever to head into an era of autonomy in space exploration,” said Simonetta di Pippo, ESA’s Director for Human Spaceflight. “Thanks to its flexibility, we can think of a wide variety of new space vehicles. ATV could evolve into a future reentry spacecraft to support future orbital infrastructures and exploration missions, carrying people and supplies to lunar orbit.”
The successful mission was very important for ESA and its partners, added di Pippo, “After the withdrawal of the Space Shuttle, ATV will be the largest servicing vehicle left to support the Station and it is our responsibility to deliver a proper service,” she noted.
“We are contributing to the largest international cooperation ever conducted in the field of science and technology,” said Jean-Jacques Dordain, ESA’s Director General. “We have a lot to learn here, not only through scientific research conducted onboard, but also with the ongoing space operations, in order to meet the challenges of tomorrow. The succession of vehicles recently launched to the ISS gives an idea of the level of joint operations the Station generates now that it is fully operational.”
ATV Johannes Kepler was launched by an Ariane 5 from Europe’s Spaceport in Kourou, French Guiana, on 16 February. It will remain docked to the Station until June, serving as an additional module, providing a shirtsleeve environment for the astronauts and reboosts to move the complex to a higher altitude.
In the coming hours, the Station crew will open the hatch and enter ATV’s pressurized cargo module to unload some 1760 kg of dry cargo, including food, clothes, and equipment. They will also pump 860 kg of propellant and 100 kg of oxygen into Zvezda’s tanks.
ATV can carry about three times as much payload as Russia’s Progress cargo ships. However, most of this load on Johannes Kepler is propellant for its own thrusters for periodic Station reboosts to compensate for atmospheric drag.
If required, ATV will also provide Station attitude control or even move the outpost out of the way of potentially dangerous space debris.
The docking of Johannes Kepler will be followed by NASA’s docking of Space Shuttle Discovery, carrying the European-built Leonardo Permanent Multipurpose Module. With Europe’s ATV and Leonardo, the US Shuttle, Japan’s HTV-2 and two Russian Soyuz and one Progress docked simultaneously to the Station, the orbital outpost will set a new record for a manned space vehicle: it will provide more than 1000 cubic meters of pressurized volume and total more than 500 ton.
See related story, European Space Agency to Launch Robot Freighter.