Session
Technical Session VIII: New Mission Concepts
Abstract
Past attempts to map the earth's electrical field have been severely limited by the lack of simultaneous global measurements. Previous measurements have been made by sounding rocket and satellite borne sensors, but these measurements have covered only singular points in the field. These satellite observations are augmented by ground radar (incoherent scatter) plasma drift measurements; however, only six ground-based installations are producing such local electrical field maps. The expansion of this ground-based radar network to meet a global objective is politically and financially impossible. Global electrical field maps constructed by forcing mathematically formulated models to fit this limited set of data points are not only inaccurate, but the degree of inaccuracy is impossible to evaluate. This paper discusses the design of a global electrical field sensing system to be deployed in a constellation of microspacecraft. Each microspacecraft incorporates a deployable sensor array (5 m booms) into a spinning oblate platform. Global deployment of 48 spacecraft is achieved through perturbation-driven dispersion of multiple spacecraft launched from eight Pegasus launch vehicles. The mass of each spacecraft is less than 25 kg, and the power requirements are less than 10 W; all the required power can be generated by solar cells covering the exterior of the spacecraft. The program costs are estimated to be less than $100 million.
Microspacecraft and Earth Observation: The Electrical Field (ELF) Measurement Project
Past attempts to map the earth's electrical field have been severely limited by the lack of simultaneous global measurements. Previous measurements have been made by sounding rocket and satellite borne sensors, but these measurements have covered only singular points in the field. These satellite observations are augmented by ground radar (incoherent scatter) plasma drift measurements; however, only six ground-based installations are producing such local electrical field maps. The expansion of this ground-based radar network to meet a global objective is politically and financially impossible. Global electrical field maps constructed by forcing mathematically formulated models to fit this limited set of data points are not only inaccurate, but the degree of inaccuracy is impossible to evaluate. This paper discusses the design of a global electrical field sensing system to be deployed in a constellation of microspacecraft. Each microspacecraft incorporates a deployable sensor array (5 m booms) into a spinning oblate platform. Global deployment of 48 spacecraft is achieved through perturbation-driven dispersion of multiple spacecraft launched from eight Pegasus launch vehicles. The mass of each spacecraft is less than 25 kg, and the power requirements are less than 10 W; all the required power can be generated by solar cells covering the exterior of the spacecraft. The program costs are estimated to be less than $100 million.
