NASA is preparing for a number of worst-case scenarios that could leave the International Space Station (ISS) without a crew for an extended period of time.
Indeed, U.S. astronauts Ron Garan and Mike Fossum told reporters they have already begun "minimal preparations" for such an eventuality - primarily by recording instructional videos to quickly train future space station staff.
The specter of temporarily abandoning the $100 billion station was first raised in August, after an ISS-bound Russian space freighter disintegrated over Siberia and forced Moscow to ground its Soyuz carrier rockets.
Although Russian officials claim to have identified the cause of the failure (a malfunction in the engine's gas generator), the loss of the ship seems to have prompted Moscow to consider the possibility of ending its permanent human presence in space.
Efforts to ferry a fresh crew to the station are further complicated by the fact that the U.S. recently retired its shuttle fleet - well before privately funded space corporations were ready to assume responsibility for manned space flight.
"You have to start working right now to say 'what if? There are a lot of efforts going on to look at all of the different options that could possibly come into play," said Fossum.
"It is possible that we will have a station without people on it for hopefully [only] a short period of time. We haven't started anything specific up here pertaining to that except for maybe documenting some of the things that we do on video so we that can use video products for part of the training for the next crew."
According to Fossum, NASA is currently in the midst of the "preliminary stages" of determining how an unmanned station would function.
"[This includes] what ventilation we're going to leave running, what lights we're going to leave on, what condition each particular experiment will be on, every tank, every valve, every hatch. The space station does require some care and feeding, and so it's important for us to be here if we possibly can.
"If that's not possible and we have to shut it down for a little while, we're going to do our best to leave it in the best possible condition to make it through that down time, and have it prepared for the next crew to open the doors, turn on the lights and come on aboard," he added.