Adam Aulick wrote:

What is the black object that appears to be pasted to the outside of
the canopy in this image? Some kind of relative wind indicator?

Yes. A simple woolen string. It's the main instrument of a glider pilot.
You may ask why a string and not the ball? First, the string is *way*
more exact than the ball and second, it's a HUD (head up display).

Stefan