Advanced Nano Telescope

Abstract

Recent developments in satellite industry gaining strong attention are so called nanosatellites. These small satellites, with sizes of about a milk carton, are easy to build and much more adordable, promising great advantages for future space missions. Up until today no reliable mid-resolution Earth observation instrument has been build that can be operated on such a small, low cost satellite. In light of these events this years Design Synthesis Exercise group 9 developed such a camera system which is called the Advanced Nano Telescope (ANT) providing a novel instrument that can be carried as payload by nanosatellites. The novelty lies in the applied principles of miniaturization and intelligent distribution in order to compete with a single large scale instrument. The strength of the instrument developed lies in the fact that it can take images with 7.5 meter resolution, requiring a volume of only 10 x 10 x 15 cm at an estimated cost about EUR 100,000. The small dimensions allow it to ft into half a standard 3 unit CubeSat such as the Delfi-n3Xt. The resolution is achieved by limiting the system to sense a narrow band around a single color, making use of a well designed combination of lenses and mirrors folding the light path enabling a long focal length. The thermo-mechanical design is designed such that the instrument functions in the hostile space environment from altitudes of 540 to 1440 km altitude. ANT has a smart modular structure that allows a mission designer to simply purchase the instrument and plug it into a satellite. Since all required electronic components are already present in the instrument the host satellite only needs to provide power and pointing capability to be able to achieve a fully functional system. One ANT by itself can take mid-resolution mono-chromatic images, but its real value will show when it is launched in a constellation, something which the low cost per unit allows. Multiple constellations of ANT's can outperform single satellites systems with similar ground resolutions in terms of development time, construction costs, operating costs and revisit time, enabling color composite imagery and promising improved availability at a lower price per image. Furthermore dedicated relay satellites can be added to achieve higher data rates. Overall catastrophic failures are eliminated as multiple satellites performing independent tasks are present offering redundancy and the possibility of replacement. The conclusion is that the system developed holds a promising future with a wide range of possible applications. The instrument itself is striking due to its apparently simple but intelligent and robust design enabling Earth observation without the need of expensive large scale satellites. For future work it is recommended to further develop the concept in order to prototype and test the actual performance of the ANT instrument.