In-space observatory testing and ground-based integrated modeling for system verification

摘要

As envisioned space-based telescopes, observatories, and constellations of sensors grow in size and complexity, the ability to perform complete ground verification becomes increasingly difficult or impossible. Integrated system modeling offers one bridge in analyzing the expected optical performance and metrology of extended platforms in space to an accuracy exceeding the optical testing that can be performed in 1-g. In addition, some aspects of the final integration and system performance testing will eventually progress to on-orbit operations in the not-to-distant future as the infrastructure for lunar and Mars manned exploration proceeds. Specifically, the possibility of an Earth-moon L1 Gateway or a similar "shipyard" in space opens up the potential for some final optical characterizations being performed in space while additional human or robotically assisted alignments and integrations can be performed prior to final deployment to distant operational destinations such as at the Earth-Sun L2. Programs like Laser Interferometer Space Antenna (LISA) and Terrestrial Planet Finder (TPF) are examples of missions where sole reliance on ground optical testing will be extremely difficult, impossible, or inconclusive. Spitzer is a recent example where modeling was a key component of predicting temperature environment and corresponding performance. The future will require a greater reliance on modeling and, where warranted, optical testing and final alignment utilizing on-orbit test facilities. In fact, the case can be made that system modeling will need to be embraced more strongly if space-based assembly and test are to be realized. The necessary analytical tools, verification ground testbeds, and confirming flight experiments are crucial along with the planning that will take full advantage of the flexibility of final system verification at a Gateway prior to a low energy transfer to the observatory's final deployed operating orbit.