The re-docking of the Russian Progress M-15M resupply spacecraft to the International Space Station (ISS) has been postponed due to an apparent failure in the new Kurs-NA rendezvous system, NASA said.
The unmanned space freighter, which arrived at the ISS in April, undocked from the station early on Monday in order to perform a series of engineering tests during re-docking designed to verify an upgraded automated rendezvous system.
The vehicle initially separated to a distance of about 100 miles from the station and held position for 24 hours before the failed attempt to dock with the ISS early on Tuesday.
The failure of the Kurs-NA system triggered a passive abort - a standard procedure that took the Progress spacecraft to a safe distance of about 1.8 miles below the space station where it will remain until another attempt is made to re-rendezvous with the ISS.
The next earliest attempt at a docking could be made later today if the International Space Station Program makes a decision to postpone the docking of the Japanese HTV3 resupply vehicle, which is due to arrive at the orbital station after the Saturday launch.
