Figure 15. Diagram of the planned trajectory of the Galileo spacecraft which will release an entry probe for penetrating Jupiter's atmosphere and will then go into a durable orbit about Jupiter for an extended study of the magnetosphere and atmosphere of the planet and the surfaces of its four major satellites. The expected date of arrival at Jupiter is 7 December 1995. Two of the major scientific instruments on this spacecraft were designed, developed, and built by University of Iowa groups headed by Professor Louis A.Frank and Professor Donald A. Gurnett.