I was sitting in my back yard about 10:30 P.M. on June 15, 2016 when I looked up and saw a white light moving South, South-East. It looked like a plane except the light did not flash or pulsate and there were no colors. It moved faster than a normal plane but maybe as fast as a fighter jet. After moving in a straight line at a steady speed for about 20 seconds it faded out within the next 4 seconds, becoming unperceivable against the night sky. It could have been a military jet at high altitude burning its afterburners for a short duration but there was no sound and no light after it faded. Also, I don't know how long it was illuminated before I noticed it. The sun had set not long ago and the object was slightly in the western sky, so it might have been the sun reflecting off the bottom of a satellite until it reached a sharp enough angle to go dark. I don't know what it was, but planes don't fade out unless they change directions. And, it didn't have extreme movements like is mentioned in typical UFO reports. I watched the video of the lights seen by the group on June 4, 2016 in the Arizona desert and it looked very much like that. I have seen a similar light about a year ago in the same area, but thought it was either a satellite or a slow moving meteor that burned out. Since I watched the video of the recent Arizona incident, I thought I might mention it to MUFON. It didn't seem extremely unnatural or man-made, so I wouldn't be surprised if it was something unremarkable. Thank you and please let me know what you think.