ufos

hi ,im an amateur astronomer and military aicraft spotter.i regularly sit in back garden with my zeiss 10 * 50 binos,sweeping the sky over coventry.
on 3 or 4 occasions this summer ,i have caught sight(in my binos) of white glowing dots,travelling in a different direction to the wind.on 15 may this year,at around 5 pm,i saw a pinkish white crescent (looking north at an elevation of about 70^)it was tiny,even with 10 power,and moving slowly toward the zenith.as it flew overhead,it changed shape into a white ,vertical line,then changed to a small white dot.maybe 3 minutes had passed by this time,and i was leaning backwards in my chair to keep it in view.the object then started to dim for a second then go back to original brightness,then dim again the same as before!!(just like flashing,but the complete opposite!!).i can only conclude that the object was SELF-ILLUMINATED!!! i was by this time nearly falling backwards in my chair,so i decided to quickly turn my chair round to try to keep the object in view.bad mistake,never found it after!
no way was this object an aircraft or satellite,or weather balloon.just the way it changed colour and shape rule out easy explanations.
i truly feel that if more people regularly scan blue skies with binoculars,then more of these strange white dots will be seen.
thanks for your time reading this!!!
take care,phil