A distinct, tight stream of colored lights (18+) in a straight line moving slowly across sky-definitely not planes-Never seen before

Seen over the area of Lebanon, Oregon, moving from west to east—a stream of bright lights traveling relatively slowly in a straight line with a white “head” and a tight straight stream of distinct, (at least 18) various colored lights (about 2 “fingers” long) following behind—high in the sky but lower than a high flying jet. Clear sky. No evidence of any flaring out like a rocket reentering the atmosphere and the lights did not separate out. The lights appeared to be all connected in a straight line. Two witnesses watched for about 3 minutes from the time we first saw them until they passed out of sight. In our many years of sky watching my Coast Guard veteran husband and I have never seen anything like it! I am a retired College employee with a longtime interest in astronomy.