| Popis: |
To date small satellites have tended not to compete directly with the capability of traditional larger, more expensive spacecraft, instead filling niches or simply offering less capability where operators needs (and budgets) are smaller. Recently, however, Earth Observing small satellites have been closing this performance gap and are now competing more directly with their bigger rivals. In particular this paper will discuss how a new, agile sub-metre imaging platform will be able to deliver an Earth Observation capability close to the limit of what is currently available in the commercial market. This platform is an evolution of the recently built NigeriaSat-2 spacecraft, which is due to be launched later this year. Achieving this level of performance within the constraints of a small satellite creates new challenges in maintaining the quality of image products. The emerging technologies used to meet these challenges and the ways in which they are combined into a small satellite solution is described. These technologies vary from novel mechanical design solutions to compact, low-power high-performance attitude sensors. What little shortfall that remains in EO small satellites' ability is primarily coverage, which can be overcome using constellations where necessary. This paper will also discuss how multiple small satellites can work together to achieve the same result as complex imaging modes of larger spacecraft. A further advantage that has been demonstrated by the Disaster Monitoring Constellation is that several agencies can pool limited resources to create a more capable shared facility. An explanation of how this experience can be translated to sub-metre Earth Observation will be given. |
