Vandenberg Delta IV Heavy rocket launch 1/20/2011

[santabarbaradotcom]

This launch was unusual (read: boring) in that it only briefly had a trail. Usually the rocket trail starts from the ground and goes all the way across the sky.

[utadamy]

@santabarbaradotcom The visibility of rocket also somewhat depends on the propulsion system of the first stage. Solid Rocket Boosters (like those on the shuttle and some variants of the medium Atlas V and Delta IV) will give a much more pronounced "trail" from the ground because of the chemical make-up of the motor. Cryogenic liquid engines, like the 3 on the Delta IV Heavy, burn Hydrogen and Oxygen and are therefore much cleaner.