Gravitationally bound geoengineering dust shade at the inner Lagrange point

► We investigate using dust clouds at the first Lagrange point for geoengineering. ► Model the zero-velocity curve in the four body problem using an asteroid at L1. ► The reduction in insolation at Earth is found and compared to 1.7% requirement. ► Largest near Earth asteroid, Ganymed, can reduce the insolation by 6.58%.