Ooops on a solar panel

Carl went up to clean the solar panels a few days ago (we use the solar panels to keep our batteries charged -- even though we are plugged in to shore power, we use the batteries to run 12V loads on the rig -- lights, water pump, ceiling fans). He found that one of the solar panels has shattered:

It may not be obvious in this picture, but the panel has a burned-looking area and the glass is shattered....

... here is the burned area -- it appears to us that maybe something fell onto the panel breaking connections and causing arcing. You can also see the shattering, though it may just appear that the panel is dirty -- it isn't, that's the shattered glass.

Another view of the panel - the damaged part is in the center on the left side in this picture.

We are not sure when or how the damage happened -- we're surmising something falling on the panel, but it could have been, maybe, jarring that happened on rough roads this summer. We know that we were on the roof at some point during our summer journeys, but we don't know exactly when -- and if I was up there but not specifically there to clean or inspect the solar panels, it is possible that I would not have noticed it (I'm not as observant as Carl is!).

The panels are wired serially, and we're still getting power into the solar controller, so the damaged panel is still letting at least some power go through. We're planning to replace the panel this winter season while we're in Mesa so we'll have a full complement of solar power when we're boondocking in the future.