The undocking planned for ATV-3 at 00:35 CEST on 26 September was postponed due to a technical problem in the data link between the Russian Service Module and ATV.
Edoardo Amaldi is safe and in dormant mode, and a new undocking date will be announced when known.
The issue was discovered by Space Station crew shortly before undocking, when astronauts attempted to send a command from an undocking control panel in the Russian Service Module to ATV-3.
The command should have been received by ATV (via the proximity link, a direct ATV-to-International Space Station radio link). Receipt of the command was not confirmed, and undocking was therefore suspended. Teams at ESA, NASA and Roscosmos are now troubleshooting the problem to determine its source and a fix.
Power and data connections that had already been disconnected between ATV and the ISS in readiness for departure were reestablished by mission controllers at ESA’s ATV Control Centre in Toulouse.
“The joint ESA/CNES mission operations team reacted professionally and skilfully to this unexpected delay, and engineers immediately set to work to replan the undocking and reconfigure ATV into a safe mode while we and our international partners troubleshoot the issue,” said Massimo Cislaghi, ESA’s ATV-3 Mission Manager.
There is no rush to undock the vessel: the Space Station and ATV are safe. Edoardo Amaldi is now in dormant mode.
A new undocking date will be announced as soon as known; there are undocking slots on 26 and 27 September.