Revolution in Demand and Supply during Last 10 Years in Small Earth Observation Satellites

While Earth observation applications were dominated by conventional large satellites in the past, rapid advancement in COTS technologies enables relatively smaller satellites to meet certain needs, limited but sufficient to some extent, with reasonably low investment. Ten years ago, the most of small satellites were developed to acquire necessary technologies, or to utilize them as space test beds to verify new technologies or components. However, recently launched small satellites start to draw attention from commercial companies who are considering the small satellites as adequate tools for their businesses. It is already demonstrated that a small satellite which weighs 200 ~ 300 kg is able to produce quality images with the spatial resolution of approximately 2 meters and soon expected to achieve 1 meter. Considering the unique advantage of satellite constellations in terms of revisit, it is anticipated that small satellite constellations would complement conventional ones in the next few years. 1. CONVENTIONAL EARTH OBSERVATION SATELLITES Table 1 summarizes conventional Earth observation satellites carrying optical sensors launched recently and to be launched in the near future. It is noted that the most of them are aiming for very high spatial resolution and they are dominated either by commercial programs such as WorldView, GeoEye, and EROS or government programs such as French Pleiades, Korean KOMPSAT, Chinese-Brazilian CBERS and so forth. The primary direction of users’ needs and technology advancement would not be changed from higher spatial resolution during the next decade [1]. Table 1: Conventional Earth Observation Satellites Launched and Planned (Optical) Country Satellite Mass (kg) Launch Year Resolution (m) Swath (km) PAN MS (# of Ch’s) USA WorldView-1 2,50