Sitting outside enjoying warm az evening looking toward west. noticed what looked like a large green navigation light fly past to my right side heading west going too fast and making no noise. i didn't see it for more than 5 seconds before it passed behind trees in my field of view. i was trying to imagine what it was, as i constantly see aircraft heading to and from deer valley airport at about that angle, but i always hear some motor noise.
not half a minute later the light came back heading east. i got out of my chair and quickly walked to the front of the house to follow it, and it went out of sight to the east in fewer than 15 seconds.
i've timed departing airliners and i can see their lights for longer than a minute from the time i first see them until i can't. this light took less than 15 seconds.
i didn't have much reference for elevation but during the sighting there were three airliners visible in various directions, a helicopter, and a small plane. the green light seemed to be higher than the helicopter and small plane, but not necessarily higher than the airliners.
on the first pass i imagined i just might have missed the sound, but there was no mistaking the silence on the second pass.
