They are the Aliens sending you your Lotto numbers...
Actually, they are probably “artifacts” of the Google Earth graphics program.
Anyone know for sure, one way or another?
Artifacts...
Heh. If I had Google's dough, I would have a less buggy product.
Think about it. Draw the figure by starting at 6 o'clock, proceed straight up to 12, thence to 9, thence toward 3 o'clock. Now veer up northeast and come down exactly where your vertical meets your horizontal.
That doesn't seem like a pattern your graphics program can't help but execute.
I searched for explanations online, didn't find any. Which is Google's raison d'etre, helping you find answers. :(