My goggles popped off during one of my jumps this passed summer. It was just very uncomfortably and your eyes water, that's all. I know a lot of people that don't wear goggles for lower altitude jumps where they open their chute shortly after exiting the plane.

-I've never encountered 'stray particles' in the sky...gravity makes sure they stay on the ground

If you stick your head out the car window while traveling about 100 mph you will get an idea.

Wear goggles or a face shield on your helmet.

I don't skydive but my guess is that particles and bugs and stuff would fly into your eye at a very high speed and damage it. Also air blowing on your eyes at that speed for that long will probably dry them out.

Your eyes water. alot!! And could be damaged by a stray particlecarried in the air.