Ready for Launch

The Titan IVB/Centaur carrying the Cassini spacecraft and its attached Huygens
probe stand at Cape Canaveral Air Station's Launch Complex 40, awaiting
liftoff. Clearly visible in this view are the 66-foot-tall, 17-foot-wide
payload fairing atop the vehicle, in which Cassini and the attached Centaur
stage are encased, the two-stage liquid propellant core vehicle, and the twin
112-foot long solid rocket motor upgrades (SRMUs) straddling the core vehicle.
It is the SRMUs which ignite first to begin the launch sequence.