Command and data handling systems for a multi-instrument sounding rocket payload

Abstract

To improve our physical understanding of the solar transition region, the Multi-Order Solar EUV Spectrograph (MOSES) has been developed at Montana State University to perform imaging spectroscopy of the sun at extreme ultraviolet wavelengths. Launched first in 2006, the instrument performed simultaneous imaging and spectroscopy over a narrow band centered around 30.4 nm. The amount of science that can be accomplished with the instrument is limited by its optical bandwidth, which must be small to reduce ambiguity in its data. This limitation can be overcome by launching an array of instruments operating at different wavelengths, piecing together a comprehensive view of transition region activity on a wide bandwidth. However, the command and data handling (C&DH) system on the current MOSES payload cannot support multiple instruments, and a new system must be built to support the addition of more instrumentation. To this end, designs based on a centralized computer topology and a distributed computer topology have been created for a new C&DH system to support the existing MOSES instrument, an EUV Snapshot Imaging Spectrograph (ESIS) and an improved guide scope. It was found that the frame rate of the entire electro-optical system was limited mostly by the low sensitivity of the optics, and that the choice between the two is driven by the mass of the system and the amount of engineering effort required to build the system. The centralized system was found to be both lighter and easier to build, and therefore a centralized system is recommended for the second revision of the MOSES payload.