Circular florescent pulsating light.My wife and I were traveling to visit relatives in Mississippi on July 17th . At approximately 11:00 PM we observer a strobe like light ahead of us . We drove approximately 4 or 5 miles with the light in sight. At this point we could see the pulsating light to our left over a field adjacent to the highway. My wife was able to look out the side window of the auto and see a circular object that was emitting a florescent like light (white). There was no sound associated with this sighting.We were able to observe the object through the rear view mirrors after we passed the object.