unity3d - Animate a lens flare in Unity when the Camera is not moving -

i have problem animate lens flare when camera not moving. achieve following effect : light behind sphere, , lens flare associated light should rotate without camera movement. right now, need move camera if want flare animate itself.actual flare can see if flare behind sphere source point not hidden object.

traditional lens flares don't rotate. watch this video.

as can see, prominent flare line stays @ same angle relative screen, when rotates camera. rotation effects might see new flares appearing , disappearing rotates camera, rolling off camera lens' curved surface.

rotating flares irrealistic. if camera , lightsource doesn't change position, lens flare shouldn't change. little research few great-looking, cinematic quality flare packs can found on asset store(like easy flares pro or proflares).