A Russian Progress supply ship has been successfully re-docked to the International Space Station after an initial re-docking failed. The ship has been at the station since April and it was undocked on July 22 to perform a series of engineering tests during re-docking to make sure an upgraded automated rendezvous system was working. However, the new Kurs rendezvous system, Kurs-NA, failed and the re-docking was aborted. After directing the ship to move to a safe distance away from the ISS, engineers assessed the problems, and then successfully completed the re-docking on July 28.
Complicating the decision of when to try the re-docking again was the arrival of the Japanese HTV-3 supply ship, which arrived on July 27. Russian engineers decided to wait until after the
HTV was successfully berthed
using the station's Canadarm-2 before a second attempt with the Progress. All systems worked perfectly on the second try.
The Progress, which is loaded with trash and items no longer needed on the station, will undock for good on July 30 and will depart the vicinity of the station for several weeks of tests by ground controllers before being sent into a destructive reentry over the Pacific Ocean in late August.
Caption: A Progress resupply ship approaching the International Space Station. Credit: NASA