This spacecraft is an engineering test article of the Large Probe portion of the Pioneer Venus Multiprobe mission of 1978. On this mission four instrumented atmospheric entry probes were carried by a spacecraft bus to the vicinity of Venus and released for descent through the atmosphere to the planetary surface. Two Small Probes entered on the nightside and a Small Probe and this Large Probe entered on the dayside of the planet. A sister mission, Pioneer Venus Orbiter, also placed a spacecraft in orbit around Venus. Simultaneous measurements by the Probes and Orbiter permitted relating specific local measurements to the general state of the planet and its environment as observed from orbit. The total cost of building and operating the probes was $83 million.
Launched on August 8, 1978, the Pioneer Venus large probe was released on November 16, 1978. This probes entered the Venus atmosphere on December 9.
Transferred from NASA to the Museum in 1984.
Transferred from National Aeronautics and Space Administration