Alexander Skvortsov, Tracy Caldwell Dyson, and Mikhail Kornienko will remain onboard the International Space Station (ISS) at least one more day as a result of problems encountered trying to undock their Soyuz TMA-18 spacecraft from the Poisk mini-research module.
At 11:12 p.m. CDT Thursday, the Mission Control Centers in Houston and Moscow concurred on a plan to reopen the Soyuz hatches, allowing Skvortsov, Dyson and Kornienko to reenter the station. The planned undocking was prevented when commands being sent to disengage the hooks and latches holding the Soyuz TMA-18 failed. The spacecraft remains securely docked to the Poisk module.
Engineers are continuing to troubleshoot the problem. Expedition 25 commander Doug Wheelock and flight engineeers Shannon Walker and Fyodor Yurchikhin sent down video and still photos of a small star-shaped gear with two broken teeth, and experts are evaluating whether the part is related to the commanding problem.
Flight controllers are tentatively aiming to retry undocking at 9:02 p.m. CDT Friday, resulting in a landing at 12:22 a.m. CDT Saturday, or 11:22 a.m. local Kazakhstan time.