The LASSII Program: Objectives, Spacecraft Design, and Mission Scenarios for Full-Scale, Shuttle-Launched, Free-Flyer Operations.

摘要

The LASSII concept is simple, but fundamentally different from that of any past or present satellite mission: to employ a sortie-mode free-flying satellite which is launched and recovered by Shuttle, and instrumented with a complement of plasma diagnostic tools which have been specifically designed to spatially and temporally resolve all active elements within an ionospheric irregularity and determine associated effects on relevant military channels. The satellite, configured for maximum flexibility as an investigative platform, will co-orbit in tandem or in overflight with a Shuttle-borne plasma diagnostics complement, making possible separation of space and time dependencies and allowing important determinations of growth and transport mechanisms in turbulent ionospheric plasmas. The satellite will be able to execute Hohmann and Crocco maneuvers with complete flexibility for selection of time spacing between Shuttle-borne and LASSII free-flyer measurements of a given ionospheric volume while satellite-to-ground and satellite-to-satellite systems tests are executed. The uniqueness of the LASS II concept makes it compatible with all Shuttle orbits from 200 to 1000 km and for all inclinations. The nature of the program, with emphasis on naturally occurring as well as artificially produced ionospheric irregularities, is also easily accommodated by Shuttle regardless of season or solar conditions. Program planning will focus on short-duration (7 to 30 days) experiments which will take advantage of built-in flexibility in the LASSII payload complement. The experiment duration will help develop efficiency through a concentrated approach to research problems designed to provide near-term solutions to issues of immediate concern.