Space freighter plunges into southern Pacific

Posted by Kate Taylor

Europe's unmanned ATV 2 space freighter Johannes Kepler burned up on reentry early this morning as planned, after undocking from the International Space Station yesterday.

Contact with the Automated Transfer Vehicle 2 was lost at 8.41pm GMT (3.41pm ET) at an altitude of 80km, just before the vehicle fell into the  southern Pacific Ocean.

There was one unplanned manoeuvre, following a warning from NASA that a piece of space debris was set to approach within 50 meters of the ship about two hours after it left the ISS. Using its last tonne of fuel, the ship fired its thrusters briefly to move out of danger.

"The mission of ATV-2 has been very smooth and we have encountered during these four months only very minor issues that were quickly taken care of by our teams," says Nico Dettmann, head of ESA’s ATV programme.

"ATV has shown again its capabilities in servicing the Station, and we are looking forward to the next, Edoardo Amaldi, which will be shipped to Kourou in August for launch in early 2012."

Just before hitting the atmosphere, Johannes Kepler was commanded to begin tumbling to make sure it would disintegrate and burn up safely.

Pieces such as the heavy docking adapter and main engines – designed to withstand extreme heat – struck the ocean at around 4pm ET. There were no hazardous materials aboard.

The freighter's last moments were recorded by a prototype 'black box' provided by the US Center for Orbital and Reentry Debris Studies. It collected information on acceleration, roll, pitch and yaw rates, temperatures and GPS coordinates.

The black box was then left to decend on its own, protected by its own heatshield, and transmitting its stored data via the Iridium satphone system.

The information will help to predict what happens to space hardware as it reenters and comes apart, and should help in designing future spacecraft so that they break up into less hazardous fragments on reentry.

"We broke many records with ATV-2," says Alberto Novelli, head of ESA’s ATV Mission Operations.

"Not only was this the heaviest payload ever launched by ESA and the Ariane 5 rocket, but the ATV’s engines also achieved the biggest boost for human spaceflight since the Apollo missions to the moon: we raised the Space Station’s orbit by more than 40 kilometres."