The Solar Shield Concept: Current Status and Future Possibilities

Author: Kenneth Roy

Description: The idea of using solar radiation management technologies to mitigate Earth’s global warming problem is not new.  The idea of positioning solar shades at the Sun-Earth L1 point is not new.  However, a number of concerns relative to this approach have been raised by various sources.  This paper will review past proposals, address the varied concerns raised to date,  examine new technologies that make this approach more viable, and outline one possible deployment scenario that could begin within the next decade. The magnitude of the task will be defined based on assumed target reductions in the Earth’s global temperature. New technologies for using solar sails for this purpose are derived primarily from NASA’s proposed Solar Cruiser (a mission powered by a 1.6 km2 solar sail) scheduled to be launched in 2025. One possible deployment scenario is discussed assuming the availability of private, reusable, heavy launch vehicles with greatly reduced costs compared to today’s launch capability. This approach can reduce Earth’s temperature rise but cannot address other environmental problems such as ocean acidification due to higher levels of CO2 in the atmosphere.  It can buy time to allow carbon neutral energy sources to be developed and deployed.  It will also result in a robust space launch capability that can then be used to facilitate space industrialization and the utilization of the massive material and energy resources available in space for the benefit of all humanity and indeed, all life on planet Earth.