Whilst out playing tennis i was talking to a friend and we both looked up to mention what a nice day it was to play tennis. then i saw 2 flying spheres quite distinct in the sky flying over us. at the start they were on top of each other in the sky and as they passed us the lower craft went behind the first as to follow the first. i remember how sperical they were and how shiny they looked. clear sky so could watch them as far as the eye could see. no other aircraft in the schnand was def not a plane as we were standing too close to see. no wind as it was a perfect sunny day and they were moving quite fast in the sky.