Very silent, white object flying slowly overhead then disappearing.I had driven out to the country to do a bit of running and other various exercises on a country road near a river bend for some good, peaceful scenery. The stretch of road I was using goes a North-South direction with a few slight curves in it (Note: This is by a small somewhat dried out river bend). I was doing a warm-up jog facing south for about 1/4 mile then turned back to run to my car where I parked it. I had stretched a bit and then turned south again to start some lunges. I noticed also that it was a very pleasant and nice day out. Late afternoon turning into evening, not a cloud in the sky, beautiful blue sky. After that realization, I noticed something white in the sky flying on a East-West route completely silent. That's what really got my attention on it and I stopped in my tracks and watched it fly by. From where I was standing, I would guesstimate it to be maybe only 400 ft above me and 500 ft in front of me. My first thought after gazing on it! and adjusting my eyesight was that it was a drone of some sort. It looked like it might of had wings but it just seemed blurry...not my sight, but the object itself. It wasn't moving very fast at all...maybe 15 mph. I don't know why there would be a drone flying above the rural countryside of Kansas with the nearest house being close to 5 miles away from my position, so I tried to rule out that it was a drone. I watched it and even waved at it slightly and eventually it disappeared like it went behind an invisible curtain or something. The thing that struck me as odd was that it was a completely still as it flew by. I don't recall any wind blowing, hearing any bugs in the grass, or any cows mooing in the distance. I didn't sense it to be anything malevolent, I was calm when watching it fly by. Couldn't tell if there were any lights on it because it was still daylight.