At exactly 6:15am, Sunday morning, the third of January,2016, I woke up and looked out of my bedroom window which is at the head of my bed. I initially intended to check the outside temp on a thermometer attatched to my window screen. It was 22° and very clear. My attention was quickly diverted to the skyline above Greencastle pike. Just above the tree line behind my house I noticed a very low flying object which basically looked liked a very bright ball of white light. I couldn't make out any shape of the craft as the light was too bright. It continued to fly very slowly in a southern direction towards Hagerstown's west end. I just assumed it was a Cessna type plane flying low on a landing approach to the Hagerstown airport and I continued admiring the clear morning sky.As I'm scanning the sky and looking at what stars, I could see, I noticed two other passenger planes flying at different directions at a much higher altitude than the flying ball of bright light I first noticed. Both of those planes displayed the blinking red lights that I'm familiar seeing.The sight of those higher flying planes made me realize that the plane that I thought was a Cessna wasn't displaying any red or blinking lights at all, just one massive light covering the entire craft. I also realized that the ball of white light was actually flying towards the center of town, not to the airport as I originally thought because of it's low altitude and speed. It was literally just ten or fifteen feet above the tree line that runs perpendicular to Greencastle pike and connects to the adjacent neighbourhood.When I gathered all my thoughts together and began to think that this thing may not be a private plane at all, I grabbed for my phone which was charging on the nightstand next to my bed with the intention to shoot some video. As I raised the phone and fumbled with video mode and focus, the light disappeared as if someone turned off a light switch. I didn't see a light trail that I would expect to see if the object had accelerated away at high speed, nor could I see a dark outline of an unlit object against the morning sky. It's as if it were erassed with no trace of it ever being there in the first place.At this point I just froze in place. I didn't know how to feel or what to think. I was just numb trying to understand what in the world it was that I just witnessed. Never in my 48 years have I seen anything in the sky that I couldn't explain.For the past few days in my spare time I've been driving around the area directly under where I observed the light trying to explain this off as something normal. There are no high mountain roads for it to have been car headlights, and I believe the object behind the light was too big to be a civilian (toy) drone.This object was in my view for exactly 5 minutes. It made no sound at all, never changed speed or color, and never diverted from its flight path before I lost sight of it. As far as size is concerned, I'm guessing that it was equivalent to the size of a private Cessna style plane, but possible a little bigger. The trees that I observed the object flying over are approximately 50-60 feet high, putting the height of the object in flight at about 75-100 feet.Lastly, I scanned the sky that Sunday morning in all directions until 7:20am, trying to relocate whatever it was that I witnessed. I've also checked the same area of sky from 5:30am until 7am the following Monday and Tuesday mornings only to find nothing out of the ordinary.