I was standing at kitchen sink and heard a odd, low-toned sound/noise that seemed close/overhead. I went out on the back deck and looked up. I saw a large, dull black area (no stars shining in this area) in sky above me. I then saw 7 red, blinking lights (4 on right side, 3 on left. Blinking in sequence up one side and down the other) around 2 sides of a triangle-shape moving low in the sky and slowly in a straight line. It flew overhead and to the SW. I lost sight of it over the near horizion of trees and buildings. I saw no lights on the back side or underneath. I was amaized at how low and slow this very large object was flying. Heard the same noise, went out onto the deck and saw it again about 5 minutes later at a greater distance, going SE flying up the mountain side to go over Sierras. Same dark shape with 8 sequentially blinking red lights – 4 on each side this time. Object did not have a light at the tip between the lights on each side. There was no other lights such as an aircraft’s wing lights. When I told husband who was in the house, he said he thinks it was a “Flying Wing” spi plane. I had an eirie, very wierd feeling watching this large thing fly so close and so slowly overhead- to the point that I thought I would find out if anyone else saw this or something like it or knows what it was.