There is very little choice nowadays, if any, for anyone in the Space sector to select a Star Tracker for Small Satellite missions suitable both on the ground of its form factor and on the ground of high end pointing performances, availability and life time. While there are a number of reputable suppliers of high end star trackers developed for large satellites, none of them had ventured thus far in the Small Satellite arena. Small Satellites have just got started to impact the long standing economic models of the space industry at large. This impact is fast expanding as these satellites can be deployed more quickly and under the frame of smaller budgets as a result of their much smaller cost base. It also bodes well in an environment of ever shrinking budgets. Sodern has made such a leap of faith in the Small Satellite growing market and has thus designed an autonomous version of the AURIGA star tracker which will be equipping the satellites of the One Web constellation. This new product has been optimized for Small Satellites, with good all-around performances and within a price range never attained before for an autonomous star tracker ordered in limited quantity. Its overall philosophy is along the lines of Plug and Play for quick and easy integration onto the platform and with the AOCS. It will help streamline the overall Operations, reduce the Assembly, Integration and Test sequences and ultimately cut the end to end satellite cost back. It will fulfdl the needs of current Small Sat missions and will also open up a realm of new demanding Small Sat missions (Earth Observation, ...) out of the reach of the star trackers of similar size available in the market place as of today. The on orbit life of Small Satellites is in the 3-7 year range compared to the more typical 7 - 15 year range of today's "traditional" satellites. The autonomous version of AURIGA will typically exhibit a 7 year life time in LEO orbit to support the longest Small Satellite missions while also easing off the end of life operations constraints (de-orbitation. ...) through its high end life time. Its acquisition and tracking robustness will authorize new missions in the field of Earth Observation, Science, etc.... through its guaranteed availability. This paper will provide a multifold approach to the autonomous AURIGA star tracker. Its architecture will be described and explained. Its operational performances will be presented and thoroughly discussed, from the weight, power and volume status to the reliability, availability and lifetime performances. The environmental characteristics will be presented and the robustness data will be addressed, such as kinematics, acquisition time, accuracy, exclusion angles and resilience to the Moon in the field of view. Moreover, we will also explain how the autonomous version of AURIGA can cope with the Sun and the Earth in the field of view through an option of multi-head management. The interfaces and the overall rationale having presided over the design choices will also be reviewed.
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