Bright flashes in north sky...I was sitting outside smoking on the west side of the house on the patio. I was looking up at the clear night sky facing north. At an altitude approximately 10,000 ft., I saw three huge flashes of white light like huge LED's in a chevron formation in the due north sky. The flashes were not an airplane and there was no noise as if any form of conventional aircraft. I kept looking in the same area and there were no more flashes for another minute or so that I could see. I could hear the neighbors' dogs barking in the distance. This is a rural area and there is no light pollution whatsoever. I came in and reported my sighting to the other occupants of the house.