ALBERT

Description: The original Cassini mission concept for intensive Saturn exploration included dual atmospheric probes - to Titan and Saturn. The Saturn probe was lost in Cassini Project cost reduction, but the Saturn atmospheric goals are still important to the planetary science community - especially it measurements can be acquired during synoptic coverage by the Cassini Orbiter. New advanced technology and design heritage from the Pluto Fast Flyby mission permit a low cost mission concept for launch early in the first decade of the 21st century, in time to take advantage of the Cassini spacecraft being in orbit around Saturn. This paper will describe such a concept. The mini-probe carrier can be a relatively simple design, depending on a solar array/battery power system design instead of Radioactive Thermoelectric Generators (RTGs) with their attendant programmatic complexities, costs, and constraints. The Atlas IIAS/Star 48B, Proton, and STS with upper stage are launch vehicle options which permit modest payload deliveries to Saturn with relatively short flight times (3 to 4 years) such that the mini-probes arrive in the time period when the Cassini Orbiter is operating at Saturn. The Cassini time-line with a compatible SMP mission sequence is described. An example mission concept includes a carrier spacecraft with three 10 to 20 kg mini-probes, launched in the late summer of 2001 by an Atlas IIAS/Star 48B on a 3.8 year trip to Saturn. Preliminary evaluation of the Cassini time-line suggests compatibility of the probe entries with collecting the data for Earth-return.

Description: MEASURE-Jupiter is a new mission concept for the exploration of giant planets, with initial application to Jupiter. By flying sets of lightweight spacecraft with highly focused measurement objectives, it is designed to break the apparent impass in giant planet exploration beyond Cassini. The MEASURE-Jupiter concept is characterized by: 1) intensive exploration of a giant planet system, 2) multiple small missions flown in focused waves using spacecraft costing $100M to $200M, and 3) mission sets launched every 2 to 3 years. Why Jupiter? Jupiter is the most complex planetary system in the Solar System with many scientifically intriguing bodies and phenomena to explore. The Galileo mission will scratch the surface of the exploration of Jupiter, posing many questions for the MEASURE-Jupiter missions to address. Jupiter is also the easiest planet in the Outer Solar System to reach, making possible flight times of 2 years and total mission durations of 3 years or less. Concept design studies have uncovered a number of scientifically rewarding, simple, low-cost mission options. These options have the additional attraction of being able to launch on 2-year trajectories to Jupiter with low-cost Delta II expendable launch vehicles. A partial list of mission concepts studied to date include: Io Very Close Flyby, Jupiter Close Polar Pass, Mini-Orbiters, and Galilean Satellite Penetrators. Key to the realization of the MEASURE-Jupiter missions is the judicious use of the new low power consuming advanced technology and applicable systems from the Pluto Fast Flyby mission spacecraft design. Foremost of the new technologies planned for inclusion are the elements of hybrid solar array/battery power systems which make it possible to perform the identified missions without the need for Radioactive Thermoelectric Generators (RTGs). This relieves the mission design of the attendant programmatic complexities, cost, and constraints attendant with the use of RTGs.