It’s only a temporary operation for the Mars rover, which has dual redundancy with ‘Side-A’ and ‘Side-B computers’, says NASA.
The rover continues to send limited engineering data stored in short-term memory when it connects to a relay orbiter. It is otherwise healthy and receiving commands. But whatever is preventing Curiosity from storing science data in long-term memory is also preventing the storage of the rover’s event records, a journal of all its actions that engineers need in order to make a diagnosis.
Funnily enough, NASA has been here before, five years ago. Side A, which the rover used initially after landing, experienced both hardware and software issues that meant the rover was ‘uncommandable’ and running down its battery.
A successful switch to Side B, however, enabled the rover to continue and also for NASA’s Jet Propulsion Laboratory engineers to remedy the issue, which was a problem with a section of Side A’s memory.
This left Side-A in a workable state again, meaning the recent ‘switch back’ can be made. Back to Side-A from Side-B…
“At this point, we’re confident we’ll be getting back to full operations, but it’s too early to say how soon,” said Steven Lee of JPL, Curiosity’s deputy project manager. “We are operating on Side A starting today, but it could take us time to fully understand the root cause of the issue and devise workarounds for the memory on Side B.
“We spent the last week checking out Side A and preparing it for the swap,” Lee said. “It’s certainly possible to run the mission on the Side-A computer if we really need to. But our plan is to switch back to Side B as soon as we can fix the problem to utilize its larger memory size.”
You can read more about about Curiosity on the mars.nasa.gov website, including recent videoes and raw images concerning the Mars explorer.