Large White/Green Object Descends over Gillette, Wyoming, No known ImpactOn December 13, approx 16:24 while traveling west bound on Clovis Point Road on the east side of Gillette near Interstate 90, a large fireball coming from the north and traveling at a low altitude descended across the sky over Gillette.The fireball appeared to be white in color, with green hued 'tails' or tracings. The ball itself appeared to be the size of a house, with the tail being 200 yards approx.It was descending at an angle, with the low side being to the south, with an excessive rate of speed in it's course.The object in question appeared to be no more than five miles before me, close enough to be viewable within clear skies. The rate of speed and angle of the object would give assumption of impact to the ground, though none was seen.There was no sound associated with the object, and impact, if such occurred, would have been south east of Gillette, though it was blocked by a hill in the line of sight. There was no evidence of its existence afterwards, as well as no known reporting.