A geostationary equivalent Polar observation system

Various potential polar observation systems are evaluated and compared against a set of requirements to develop a system capable of providing geostationary equivalent coverage of the Earth‟s high-latitude regions. Consideration is given to Non-Keplerian orbits, where it is found that the orbit altitudes are restrictively high, and traditional highly-elliptical Molniya orbits where it is found that no single spacecraft can provide observations „over the pole‟ to 55 degrees latitude of equal quality to those produced by geostationary systems. Subsequent analysis of the Taranis concept reveals the ability of these systems to adequately view the target region with a reduction in the required number of spacecraft. Mass budget analysis reveals a possible payload mass of 151 – 379 kg for a single platform launched using the Soyuz launcher to a 16 hour, 90 degree inclination Taranis orbit for an 8.5 year mission. Four spacecraft, capable of observing continuously to 55 degrees latitude using single imagery, can be launched on the Ariane 5, which results in a payload mass range of 193 – 482 kg for an 8.5 year mission.