The Pluto-New Horizons RTG and Power System Early Mission Performance

Abstract

On January 19, 2006, the Pluto-New Horizons spacecraft was launched from Cape Canaveral Air Force Station (CCAFS) with a radioisotope thermoelectric generator (RTG) as the power source and a 30V power regulation and distribution system designed and built by the Johns Hopkins University Applied Physics Laboratory. Pluto-New Horizons is the flagship spacecraft of NASA's New Frontiers program of medium-class interplanetary missions and targets the first reconnaissance of Pluto and its moon, Charon, and the Kuiper Belt. Arrival at Pluto is scheduled for July, 2015 at which time the spacecraft will have traveled 3 billion miles and be almost 32 AU from the sun. Due to the extended mission duration and extreme distance from the sun, a RTG was chosen as the spacecraft's power source. RTG missions place complexity on the spacecraft power system design due to their unique power characteristics and limited opportunities for test prior to pre-launch field operations. The RTG integration and test with the spacecraft results are presented along with the spacecraft power system performance during launch and in the early mission phase. These in-flight operational results demonstrate a fully functioning power system that will supply the spacecraft with safe and reliable power during the exploration of the farthest reaches of the solar system.

Statistical Reliability Analysis of Interplanetary Spacecraft Operating at Different Interplanetary Extremity

“…But the potential cause for the increased reliability behaviour at EH-Extremity may be due to the power source, i.e. the magnificent and extended operating probes like Voyager 1 and 2, and New Horizons that embraces nuclear thermoelectric generators as their primary power source which provides uninterrupted power supply throughout the mission life and enhancing reliability [22][23][24].…”

The New Horizons Mission to the Pluto System and the Kuiper Belt

“…By operating only one side of the spacecraft avionics when taking instrument data, operations can be supported until the year 2026. [9] 250 240 23 X FElight Power P-oje( (1967 -1975), the Transit Improvement Program satellites (1970 -1977), and MAGSAT (1977MAGSAT ( -1979 …”

Estimating the thermally induced acceleration of the New Horizons spacecraft

“…As previously stated, space missions that go beyond Mars rely on RTGs for power supply. New Horizons is no exception, having a single F-8 RTG, loaded with 9.75 kg of plutonium-238 dioxide [16]. The RTG, measuring about 1 m and with a diameter of 0.3 m (not accounting for the cooling fins), is linked to the main body through an adaptor collar and a support structure, which provides both thermal and electric isolation [1].…”