Intro : I am passionate about everything flying. I have a ultralight airplane licence. I am very capable of making the difference between a commercial airplane strobe, its landing beam, a satellite, a military jet, a meteorite or common stars. What I have seen crossing the sky this day I have never seen it before or since.I got up early this day and went outside my house to smoke a cigarette. The sky was crystal clear and since there's no big cities around where I live one can appreciate watching stars at night with no artificial light pollution. It happens that I was looking west since the deck outside my house is oriented this way. That's how I've spotted a very bright object (much brighter than the surrounding stars) coming from this direction. There's the Greensboro airport not far away from Winston Salem and sometimes and depending on the wind direction one can spot commercial or private jets making their approach. But they 're easily identifiable since they're flying way under 500 knots with all lights on : landing beam, strobe and green and red wings lights and the noise can not be misled for something else. Nothing of the sort for the object I have seen. The light emitted was too bright for a landing beam and the speed way above a commercial jet even at cruising speed. The altitude was very high in the sky although difficult to estimate in the beginning of my observation. I would say higher than a commercial jet and lower than a satelliteSo at first I thought it was a satellite. But I had to change my mind when I saw that the object was pulsating from the higher brightness that made me spot it in the first place to zero light emitted in a cycle of 4 of 5 seconds then returning to high brightness etc. There was clearly a pattern to it and it was not a strobe and usually the satellites reflecting sunlight on their solar panel have a constant brightness. Besides it was too big to be a satellite. So In the end of the day I don't know what I've seen that night.