Driving home on the 15 around 1:10pm after the truck weigh station, going down hill, i saw a bright silver metallic disc slow moving east then stopped, then disappeared. the object was too bright to be a plane, and too slow i first thought it was small plane being reflected by the sun making it very bright, but it hovered; thusly not a plane. the object was cigar to disc shape, very bright metallic like chrome. it was moving eastward slowly, then it stopped and hovered. i noticed it as i was trying to figure out what it was. i felt unsure. i didn't have an initial reaction other than just trying to understand what it is. the object got brighter, and just disappeared.