How can you tell which direction it going to the right or left of JFK, in a 2d photo?
No. At least as I can tell.
But it is obvious that almost all the debris was sent flying forward. Some of it up and forward. Some of it level and forward. Nothing is seen going backwards.
Which means that the droplets of blood and specks of brain matter were carried back by the wind which was blowing backwards at 18 to 23 mph relative to the moving vehicles. Which reached the trailing motorcycle officer?s. It looks like it really is a bad idea to pee into the wind.