I was heading north on aurora (99) and noticed a light in front of a jet (white- perhaps alaska air). At that original distance the jet appearred about an inch long, the light maybe a sixteenth of an inch diameter (measured at arms length holding my fingers apart).The object brightly reflected sunlight from behind me for a moment then appearred a matte metallic color. It appearred to maintain a distance of 1 1/2 jet lengths in front until I found a spot to pull over to call my girlfriend to tell her. This occurred at10:02-10:04am. There was no northbound air traffic in the area for at least 5 min. after.The jet was just west of hywy 99 and first spotted just north of n 85th. At first I thought perhaps it was a fighter escort or a film crew jet (you never know) but the characteristics were way different from those. Luckily I was on a 4 lane road with no other cars around so I could slow way down to safely look as long as I could. I also took off my sunglasses and put my head out the window to eliminate the possibility of it being a reflection. I lost sight of the object as the plane got further north and more distant and I had to pull over to be a safe driver as an intersection was ahead. I originally took notice of the jet because there was a distinct lack of air traffic at that time,just looked up and saw something odd out in front of it.