We were driving westbound on Hwy between Riverton and Fort Washakie at 1930 hours. Sky was clear and cold with a full moon behind us just rising in the east. Object appeared from over our heads and behind us moving into view in the windshield as it appeared to be falling from directly overhead to the west. When about ten degrees above the western horizon it abruptly blinked out. Object was about the same apparent diameter as the moon (NOT a reflection) and was bright green with an orange halo around it and left sparks as it descended. Would have thought it was maybe a re-entering satelite except for the way it abruptly blinked out. I am an amateur astronomer and have been a police officer for 28 years. Never saw anything like this before! Sorry I took so long to report this to you but I didn't know you existed until just now. I am always looking for interesting things in the sky but this takes the cake. Thought you might be interested. Thanks!