Mission Design and Operations: SPARTAN-Halley as a Paradigm for Small Satellites

The SPARTAN reusable spacecraft opened a new arena for innovative scientific and engineering experimentation in low earth orbit. SPARTAN\u27s a free flying, 3-axis inertially stabilized spacecraft which is deployed and retrieved by the Space Shuttle. The spacecraft is unique in that it performs all scientific observations as well as its guidance, navigation, and control functions completely autonomously. This paper will describe the innovative approach that was taken in the design of the SPARTAN guidance and navigation system for a 48-hour observation of Halley\u27s Comet near perihelion passage. Autonomous vehicle navigation techniques that utilized solar sensors, a single star tracker, a 3-axis gyro package, and two independent cooperative microprocessors will be discussed. Ephemeris development and structure will be detailed. Creative techniques used to tune the navigation and science observations with respect to the actual achieved mission orbit will also be described. Text will also be devoted to describing the vehicle and its sensor and instrument configuration. Lessons learned from SPARTAN will be discussed in the context of small satellite mission operations