Scientists plan test of technology that could dim the Sun

The Israel-based startup Stardust, registered in Delaware, is preparing to test a technology designed to reduce the intensity of solar radiation and potentially lower Earth’s temperature.

The approach mirrors the natural cooling effect of major volcanic eruptions, which release particles that reflect sunlight back into space. Stardust aims to spray engineered microparticles above cloud layers, creating a reflective shield that partially blocks solar heat.

The company has not disclosed the composition of the particles, saying only that they are safe for humans and the environment. Stardust stresses it will not deploy the technology without international approval and comprehensive risk assessment.