Ten minute stationary pulsating white light 80 degrees elevation 60 seconds between pulses 2000 MST.Observed pulsating white light for approx 10 minutes about 8pm local MST. Object pulsated at a rate of once every 60 seconds. Location of light was on a line between star Regulus and planet Saturn and then about 4 degrees to the south. Object remained stationary. To high of an elevation approx 80 degrees to be a geosynchronous satellite and not an aircraft or orbiting satellite. Possibly a pulsar but after 10 minutes it no longer flashed. I have observed a similar flashing light in the same area of the sky in the past but don't recall details or time of year.