Optimization of Inner Heliospheric Sentinels Spacecraft Conceptual Design

The Sentinels mission is a key component of NASA´s Living With a Star (LWS) program. The Sentinels Science and Technology Definition Team (STDT) has completed a study to define the science objectives, measurement requirements and observational strategies, and mission design for the Sentinels mission. The Inner Heliospheric Sentinels (IHS) are one of the three flight elements (the others are the Near Earth Sentinel and Far Side Sentinel) that make up the Sentinels mission. The four spin-stabilized IHS spacecraft are in elliptical heliocentric orbit with perihelia at ~0.25 AU and aphelia at ~0.75 AU. This orbit presents unique spacecraft thermal control and power challenges. This study has demonstrated mission feasibility by developing a spacecraft design concept using conventional technologies that satisfy the science and mission requirements defined by the Sentinels STDT. Numerous trade studies were performed to optimize the spacecraft design. The trade studies and their results are discussed.