14 DAY TRIAL // Officials with the Russian Federal Space Agency (RosCosmos) say that the Progress 47 space capsule will conduct another automated docking attempt today, July 28, using an upgraded guidance system.
The unmanned spacecraft arrived at the International Space Station (ISS) in April, delivering supplies for the lab's six-astronaut permanent crew. It remained attached to the Russian Pirs docking module until July 22, when it was undocked and sent on an orbit close to the station.
One day later, on July 23, mission controllers attempted to have the vehicle reconnect to its previous port, using the upgraded Kurs-NA automated docking system. However, the test failed, and the attempt had to be aborted.
Progress 47 was subsequently placed on an orbit that will take it very close to the station today, when a new docking attempt is scheduled. The maneuver will begin at 9 pm EDT (0100 GMT July 29). Experts hope that the glitch that stopped the first attempt will not pop up again.
Russian spacecraft, including the unmanned Progress and the manned Soyuz, have been using the previous version of the Russian docking system, called Kurs, for many years. However, RosCosmos wants to reduce the technical complexity of the overall system.
Kurs-NA uses a single antenna for data transmission, as opposed to the six used by its predecessor. This also makes it more energy efficient, if project scientists are able to figure out why it fails.
During today's attempt, the Progress 47 vehicle will first be brought to a position some 46 kilometers (29 miles) away from the ISS. Once it arrives at the designated coordinates, RosCosmos experts will activate Kurs-NA again.
If the maneuver fails, then RosCosmos will not perform another docking attempt. The space capsule – currently filled with garbage and unneeded items and experiments – will be set on a course that will see it destroyed in the upper atmosphere, Space reports.
Russian officials say that the faith of upcoming Progress and Soyuz missions is in no way affected by the success or failure of the Kurs-NA test.
The docking attempt is the last important moment in a very busy week for the Expedition 32 crew aboard the ISS. On Friday, July 27, they were on station to capture the Japanese HTV-3 robotic capsule as it flew past the station. Astronauts used the Canadarm-2 robotic arm to secure the cargo spacecraft.