In the conventional system approach, image stability requirements are met constraining the platform and instruments to a very quiet thermo-mechanical environment. Major limitations come from the difficulties to develop low noise reaction wheels and the huge mass penalty of a cold gas micropropulsion solution. For the GEO-HR mission, which targets 6-10 m spatial resolution from GEO, an active line of sight control is considered as a candidate solution.

Background and justification:

The Sun regularly releases considerable amounts of energy resulting in coronal mass ejections (CMEs) and accelerated particles, which can have a variety of adverse space weather effects at Earth and in the near-Earth environment. A useful means of tracking space weather activity is via solar radio bursts (SRBs) associated with CMEs and solar energetic particle events (SEPs); CME-driven shocks can be tracked via Type II SRBs, while energetic electrons escaping into the heliosphere can be tracked via Type III SRBs.

Space weather observations and the prediction of expected disturbances on ground- and space-based infrastructure are critical for the safety and evolution of our modern society. Space weather events, like solar storms, can have a significant impact on navigation, communication, power grids and other electrical conducting infrastructures. Therefore, space weather predictions are very important, but recently lack a reliable estimation of the geo-effectivity as well as detailed information for regions and systems potentially affected.

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