White flashing light moving rapidly and quietly across sky.

Was on back porch trying to get a look at Saturn.  Flashing white light came across sky from basically East to West.  Did not discern anything other than the light but the light was 5-6 times bigger than the surrounding stars.  It was flashing at roughly 1 flash per second.  Appeared to be low in sky and was in view for approximately 5-6 seconds.  Thought at the time it was a satellite but checked one of the websites and there were no satellites scheduled to fly over.  
No idea what it was but it was moving fast and silently.  Wife was on the porch with me but looking thru binoculars and did not see object.  Was not a lightning bug as I could clearly see the white color, lightning bugs are yellow.
Not saying extra-terrestrial, just something I never saw before.