A number of deep space probes have had solar reflector attitude control
panels. These use the photons to help stabilize or move the craft to a
new attitude using the photon momentum. There have been many proposals
over the years for solar sail propulsion for space probes.

You don't ordinarily see the effect because the pressures are very small
compared to pressures from even the most gentle breeze or air current.
But they ARE there.

wrote:

like little things like blades of grass or ants out of a tree

--
Don Stauffer in Minnesota

webpage- http://www.usfamily.net/web/stauffer