This is clearly a batch of Zinc Oxide White, used for marking out a football pitch or similar. As football pitches go, the areas around the central line and near the goal-posts become muddy sloughs, and after years of complaints the football club admits defeat and decides to re-turf the pitch. The first step is removing the existing turf. This wouldn’t be the first time a club got into this situation and ran out of money. They didn’t even clear the pitch properly in the first place, as witness the dod of turf sticking up with the white marking line still on it.
There you go. The whole business explained. But will these cliquey astronomers thank me? Oh no, they will cook up their own outrageous theories.
Nay, it is the remnants of a Martian brownie.
I’ve been to Tisdale, the land of rape and honey, in a round about way to Regina. That’s what’s left of the white stop strip on the asphalt just before the traffic light. The background does look hillier than I remember.