I was in my car driving home and had just turned from Hwy 965 onto US Hwy 61 North. As I crossed over the Thompson Creek bridge, I looked over toward the west and witnessed a large hazy light-green glowing object traveling at extremely high speed. It appeared to be heading in a north-westerly direction and it disappeared as I was driving and the treetops blocked my view. In all, the sighting lasted about 3 seconds.The object was much larger than any aircraft or star I've ever seen, and much much larger than anything that should've been traveling that close to the ground. It had just appeared in the sky, (as soon as I had looked over it had appeared) and did not stop but sped off extremely quickly.