UFO Sighting in Graniteville, South Carolina on September 30th 2015 – Strobing yellow-white light barely over tree line. no sound seen twice over 4hour time period.

Weds,Sept 30 2015: This object was seen twice within 4 hours. It is assumed to be the size of a large helicopter to small plane with a yellow white strobe light. The first time it was seen was by my mother in the East by SE sky as she was driving home around 8:30 pm. I observed this object outside my window to the SW around 11:15 pm. The object was barely clearing the tree line and flashed it's very bright yellow white light. It blinked once then flashed again 20-30 seconds later only a few feet away from where I had first seen the object it was moving very slow as it changed direction and went south. I can not stress enough that it was completely silent! It was flying so low that the flashing light lit up the ground and surrounding houses below! Had it been a plane or helicopter it would've deafening and shaken our home! Had it not been for the bright light I could've passed overhead completely unnoticed by anyone. I scoured the local news reports and weather. There was no report of a manhunt or the like. If you can uncover anything I hope you can tell me that I didn't see a UFO. I truly hope there is a rational explanation to whatever I just saw. Please contact me via e-mail if needed.