The Air Force Delta II vehicle sits poised on Complex 17A at the Cape Canaveral Air Station, ready to carry the 19th NAVSTAR Global Positioning System Satellite into orbit. A secondary NASA experiment, the Small Expendable Deployer System (SEDS), will also be deployed.

Small Expendable Deployer System (SEDS) is a tethered date collecting satellite and is intended to demonstrate a versatile and economical way of delivering smaller payloads to higher orbits or downward toward Earth's atmosphere. 19th Navstar Global Positioning System Satellite mission joined with previously launched satellites used for navigational purposes and geodite studies. These satellites are used commercially as well as by the military.

This illustration of the Comet-Shoemaker/Levy collision shows the first piece of the remains of the comet crashing into Jupiter. This event occurred in 1994 after tidal forces from Jupiter caused the comet to break up into 21 separate pieces. Although on a very different scale, the physical mechanism for the breakup of Shoemaker/Levy also caused the tidal disruption of the star in RX J1242-11. (Illustration: SEDS/D. Seal (edited by CXC/M. Weiss)