Thermal Performance of Parker Solar Probe through Orbit Eighteen



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2024 International Conference on Environmnetal Systems


The Parker Solar Probe (PSP) spacecraft has successfully completed eighteen of 24 solar orbits that have explored the inner region of the heliosphere through in-situ and remote sensing observations of the Sun's magnetic and electrical fields, plasma, and accelerated particles. So far during the 7-year primary mission that launched on 12 August 2018, the spacecraft has experienced a wide range of hot and cold thermal environments. To date, PSP has performed nominally during the eighteen perihelion encounters and the six Venus fly-bys that have included two with 11-minute eclipses. The extreme solar constant experienced during the mission minimum perihelion required the development of two revolutionary thermal technologies: (1) to actively cool photovoltaic solar arrays and (2) to passively protect the spacecraft from the intense solar heating without changing shape or insulating performance when the sun-side temperature reaches nearly 1000 °C. The maximum heating from the sun's corona region, when the spacecraft reaches the minimum perihelion distance of 9.86 solar radii (RS / ~475 earth suns), will occur during the final three orbits. Key to spacecraft electric power generation and overall mission success are the actively cooled photovoltaic solar arrays that use thermally conditioned water provided by the state-of-the-art Solar Array Cooling System (SACS) and state-of-the-art construction of the Thermal Protection System (TPS) that utilizes C-C foam sandwiched between C-C face sheets to create the very large structurally rigid and thermally insulating packaging umbra for the rest of the spacecraft below. This paper will discuss the thermal performance of the SACS and the passively cooled spacecraft during Orbit 18, when the spacecraft reached a minimum solar distance of 11.42 RS (~354 suns), and compare this performance to that measured during the previous seventeen orbits.


Carl Ercol, The Johns Hopkins University Applied Physics Laboratory (JHUAPL), USA
Krithika Balakrishnan, The Johns Hopkins University Applied Physics Laboratory (JHUAPL), USA
ICES101: Spacecraft and Instrument Thermal Systems
The 53rd International Conference on Environmental Systems was held in Louisville, Kentucky, USA, on 21 July 2024 through 25 July 2024.


Parker Solar Probe, pump loop, thermal control, solar array cooling system, PSP, SACS, Thermal Protection System, TPS