4 large wing span aircraft flying slowly in straight line eqidistance apart with flashing red and white lights.There were four large wing-span aircraft. They were flying In a straight line eqidistance apart. They had flashing red and white lights. I could hear the faint rumble of an engine, but they didn't seem that high up because the lights were so visible. They weren't moving that fast. I thought it odd they were in such a straight line, so close together in jet stream of each other and moving slowly. They appeared to be coming from the South going north. I figured they possibly could be coming from Beale AFB. It just appeared strange being in formation like that, as well.