Cone shaped light

I was on my way to work. It was dark. I was heading south on US 101 from Lakeside to Coos Bay. I spotted the light shortly after I got on the highway. It was cone shaped with the wide part toward the ground. It appeared very large but as I drove towards town it never changed in size and I didn't seem to get any closer to it. It covered a large piece of the sky bigger than several football fields. There were several other cars on the road but I never heard anyone, including myself mention it. It wasn't in the newspapres or on TV. I didn't say anything about it for more than 20 years later. I did a lot of thinking about it and came to the conclusion that it may have been the reflection of a Satellite launch in California or possibly Cape Kennedy Florida.