I was a professional private flight attendant of 20 years, flying from van nuys, california to sun valley idaho. there was only one passenger who was sleeping. flying north-east, with with the sun about 10 degree in the west, about a half-hour from sunset, and were flying at the western border of area 51. i looked out the large gulfstream aircraft window, toward the east and saw an orb, about 4 to 6 feet in diameter hovering below the starboard winglet. it was just stationary, like a scene from a bad sci-fi movie. this went on for about 3 minutes. i couldn't believe my eyes. it was silver/gold/brown in color and a perfect orb shape. i stared at it until it rapidly raced off and vanished. i went to the cockpit and asked the pilots if they saw anything on their tcas (traffic collision avoidance system), which they replied, no. they made a radio call to ground control, who told them there was no traffic in the area. after flying professionally for years, i firmly believe in outside forces in the universe, as i have now witnessed it.