EUROPA LANDER RADIATION ENVIRONMENT DEFINITION AND INITIAL SHIELDING DESIGN
Luz Maria Martinez Sierra
Jet Propulsion Laboratory, California Institute of Technology
Luz Maria Martinez Sierra is a engineer at the NASA Jet Propulsion Laboratory, she has been at the lab for 2 and a half years working in the natural space environments groups. She has experience working with radiation transport codes like MCNP and NOVICE and knowledge in nuclear physics and interactions. As part of her task she helps engineers with the dose calculation and radiation shielding design for spacecraft to help mitigate the damages.Luz Maria received a Master's degree in Engineering Physics form Embry-Riddle Aeronautical University in 2011 and her bachelor's degree in the same field from EAFIT University in Colombia.
Abstract
Any spacecraft exploring the Jovian system has to be designed to survive Jupiter’s hostile radiation environment, as is the case for the proposed Europa lander mission. As a highly scientifically driven mission concept, the... [ view full abstract ]
Any spacecraft exploring the Jovian system has to be designed to survive Jupiter’s hostile radiation environment, as is the case for the proposed Europa lander mission. As a highly scientifically driven mission concept, the Europa lander would be designed to search for evidence of life on Europa and evaluate its habitability via in-situ techniques. The lander would be expected to survive a multi-year journey to Jupiter, and then operate for at least several days after landing at the surface of Europa, located in the heart of Jupiter’s radiation belts.
As currently planned, the dose level for the lander electronics must be less than 150 krad(Si). To meet this requirement, the electronics would be housed in a radiation vault similar to that used on Juno and baselined for use on the planned Europa Multi Flyby Mission. A series of 3D radiation transport calculations and parametric studies of vault thickness were performed on a spacecraft mechanical configuration to reduce the mission total ionizing dose to desirable levels in the electronics assemblies of the Europa lander vault. Mission fluences were estimated with the latest GIRE3 model. These fluences were used as an input for NOVICE simulations, where a simplified 3D model of the spacecraft and the lander's vault was modeled. Critical units inside the vault such as instruments and on-board computers were represented as independent boxes. The results of the simulations are summarized in this presentation for the 20 worst locations inside different boxes. A preliminary radiation estimate indicated that a vault wall thickness of 10 mm of aluminum would be required, but the 3D analysis showed that a wall thickness of ~8.5 mm of aluminum would be sufficient. This corresponds to a vault mass of about 72 kg, a mass reduction of ~8 kg from the preliminary shield mass estimate.
Authors
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Luz Maria Martinez Sierra
(Jet Propulsion Laboratory, California Institute of Technology)
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William Mcalpine
(Jet Propulsion Laboratory, California Institute of Technology)
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Martin Ratliff
(Jet Propulsion Laboratory, California Institute of Technology)
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Insoo Jun
(Jet Propulsion Laboratory, California Institute of Technology)
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Michael Cherng
(Jet Propulsion Laboratory, California Institute of Technology)
Topic Areas
Modeling , Radiation Effects (e.g., SEE, TID, DDD) , Radiation
Session
Session 3 » Mission Design (14:00 - Monday, 15th May)
Paper
LanderShielding_ASEC_extended_abstract_2017_V6.docx
Presentation Files
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