On Sun, 20 Feb 2005 03:41:33 +1300, Geoff Blackmore expelled the
following:

Unexpected Cleaning Keeps Rover Rovin' 22-Dec-2004

Something (or somebody??) has been regularly cleaning the Mars rover
Opportunity's solar panels during the night, enabling the device to
continue to work much better and longer.
NASA rover team leader Jim Erickson has said that the unexplained cleaning
events have kept Opportunity's solar panels operating close to their
maxiumum daily output of 900 watt-hours. Due to a previous accumulation of
Martian dust, which is heavy and dense, output had dropped to 500
watt-hours per day.

The output of Mars Spirit's solar panels, which are not getting cleaned,
have dropped to 400 watt-hours per day.

NASA has no explanation for the cleaning.

A little late with this don't you think?

More than likely it's wind or breezes. I know some of you fruitcakes want
to believe aliens are cleaning the panels off but you need to get freaking
real.