President Elect, The Mechanic wrote on Jan 4
th, 2018 at 9:13pm:
Who Keeps cleaning the Rovers Solar Panels?
one minute the Rover dies, and hours, days, months later the Rover fires back into life with the cleanest Solar Panels you've ever seen...
like WTF?
Google is your friend Mechanic
A cleaning event is a phenomenon whereby dust is removed from solar panels, particularly ones on Mars, by the action of wind. The term cleaning event is used on several NASA webpages; generally the term is used in reference to the fact that Martian winds have blown dust clear off the solar panels of probes on Mars increasing their energy output.
The term started being used in 2004 as the Mars Exploration Rovers' (MER) solar panels started to benefit from these events. The rovers were expected to last about 90 sols (Martian days) on Mars, after which dust would cover their solar panels and reduce solar power to levels too low for the rovers to operate. However, power levels went back up due to the cleaning events caused by the winds in the Martian atmosphere. Periodic cleaning events have allowed the MERs to operate far longer than the planned 3 months. While Spirit rover finally ceased operation in 2011, Opportunity rover remains active as of 2017, more than 13 years after landing.
Cleaning events can either be rapid, such as overnight, or over many days where solar power slowly goes up.
https://en.wikipedia.org/wiki/Cleaning_eventSo it is nothing more than Martian wind