NASA's Curiosity Mars rover is taking a few days off while engineers examine a voltage change that is not a threat now, but could be if left untreated.
According to a Jet Propulsion Laboratory (JPL) press release, Curiosity's operators detected the voltage change Nov. 17 and decided to suspend the rover's activities, even though it could still operate in its current condition. Engineers will run tests to determine what caused the change before powering Curiosity back up.
"The vehicle is safe and stable, fully capable of operating in its present condition, but we are taking the precaution of investigating what may be a soft short," said Jim Erickson, Mars science laboratory project manager, at NASA's JPL in Pasadena, Calif.
A "soft" short refers to a leakage in something only partially conductive of electricity, whereas a "hard" short would mean an electrical wire came into contact with another. The Curiosity team noticed a decrease in voltage Sunday, the rover's 456th day on Mars.
A 32-volt power bus that distributes electricity to Curiosity's various systems runs the rover. The electricity level had been around 11 volts, but dropped to four, causing the team to shut down its operations and examine the cause.
Curiosity has experienced a soft short before, on landing day in Aug. 2012. Devices for explosive release used before and after the landing caused a decrease from 16 volts to 11, but its operations were unaffected since. With that in mind, the rover's team knew a soft short could cause a change in voltage.
The soft short could pose a lingering problem for Curiosity, as such issues tend to affect similar shorts in the future. The engineers will look for the root cause while Curiosity is still operational, but they did stop the rover before it entered into a "safe mode" that would have caused it to shut down most operations automatically.
