Feasibility study of the implementation of a space sunshade near the first Lagrangian point

Abstract: The lack of strong measures to avoid the possible fatal consequences of global warming is pushing researchers to look for other alternatives such as geoengineering.Within geoengineering, this study focuses on the space based solar radiation management methods. More precisely, the project evaluates the feasibilityof implementing a space sun shade near the first Lagrangian point in the Sun-Earth system within a thirty year period time from now. The study isstructured in three main blocks: spacecraft configuration, trajectory definition and launch. An analysis looking at the minimum cost system was carried out,starting with the definition of the mass and size of spacecraft. Furthermore, an optimization of the trajectory was developed in order to minimize the traveltime to the vicinity of the Lagrangian point. The shades will be formed by swarms of 10 000m2 solar sails that will cover an area of 6:3 x 1012 m2 witha total mass of around 5:7 x 1010 kg. The sails will be injected into a LEO and will start a trajectory to the vicinity of the first Lagrangian point that willtake around 2.3 years. The total cost of the project is approximated to be 10 trillion dollars. The mission appears to be feasible from a technological pointof view, with some development needed in the attitude control subsystem. The main challenge will be the launch of all the spacecraft. A space mission of thisdimensions has never been attempted before so it will require a big advance from the launch vehicle industry.