Planetary sunshade for solar geoengineering: Preliminary design of a precursor system and mission

[Geoengineering News]

https://www.sciencedirect.com/science/article/abs/pii/S0094576525003133

Authors

Marina Coco, Catello Leonardo Matonti, Chantal Cappelletti, Bruce Chesley, Christer Fuglesang, Giuseppe Governale, Nishanth Pushparaj, Marcello Romano, Gunnar Tibert, Lisa Wilk

https://doi.org/10.1016/j.actaastro.2025.05.031

04 June 2025

Highlights

•A precursor mission is proposed to validate key enabling technologies for the Planetary Sunshade System.

•The mission serves to test solar sailing, the attitude and orbit control system, and optical shielding materials at the photo-gravitational equilibrium point L1*.

•Solar sail technology is employed for propulsion, attitude control, and station-keeping.

•The control strategy exploits solar radiation pressure to maintain the spacecraft aligned with the Sun- Earth conjunction line.

Abstract

The increasing urgency of climate change mitigation necessitates innovative solutions beyond terrestrial efforts. Space-based solar geoengineering - particularly a Planetary Sunshade System (PSS) positioned near the photo-gravitational equilibrium point 

, which lies closer to the Sun than the classical L1 due to the effect solar radiation pressure - has been proposed as a potential method to reduce incoming solar radiation and stabilize global temperatures.

This paper presents the preliminary design of a precursor mission aimed at demonstrating key technologies essential for the deployment of a full-scale PSS. The proposed mission features a 12U CubeSat equipped with a 81 [m2] solar sail, which will be used for propulsion, attitude control, and station-keeping at L1. The mission objectives focus on validating the long-term performance of optical shielding materials, demonstrating solar sailing as a sustainable propulsion method, and assessing the feasibility of autonomous orbit and attitude control systems.

The technical and economic feasibility of the precursor mission, with an estimated budget of 10M USD is examined. By addressing key uncertainties in spacecraft formation flying, material degradation, and long-term solar sailing operations, this mission represents a crucial step toward the realization of a scalable planetary sunshade for climate intervention.

Source: ScienceDirect