Trends in instrument systems for deep space exploration

In recent years there have been an increasing number of space science instruments that are being designed as integral elements in integrated instrument suites as opposed to stand-alone instruments. In fact, some instruments are becoming closely integrated with the mobility systems that carry them to their science targets. This higher level of integration has been motivated by both resource limitations and by an increased focus in science investigations. The reduced size and budget available for individual space science missions combined with the increased complexity of these missions, has encouraged instrument developers to greater integration to reduce mass, volume, and power needs. In parallel, NASA has shifted focus from flyby and planetary orbiting missions, which primarily included remote-sensing instruments, to various types of landed vehicles, which include primarily; in-situ instruments. Initial studies of the planets on planetary scales have moved to more detailed ground truth studies on planetary surfaces. The science goals have shifted to focus on specific questions, in the case of Mars, understanding the history of water and the possibilities for life on the planet. This increased science focus has, in turn, created the need for integrated science suites that can address these questions in ways that stand-alone instruments cannot. This paper discusses a number of NASA instrument suites, ranging from those currently operating in space to those that are in early study phases. The focus of the discussion is on the trends, including the shift to greater integration, the concomitant challenges that must be overcome to achieve this integration and the benefits that can ensue. This is not intended to be a comprehensive examination of new instrument suites (that would be a much longer paper) rather, the example NASA instrument suites discussed were selected, from those that the author had some familiarity with, to include suites representative of the trends in instrument systems for deep space exploration.