Moon-dust shield could help fight climate change on Earth
In recent research, they propose mining, scooping and blasting dust from the moon's surface and placing it between Earth and the sun, where the newly placed clouds would shade our planet for a few days before solar wind and radiation pressure dispersed them. In a year, researchers say, such dust shields could reduce Earth-bound sunlight by 1.8%, which falls within the range needed to slow our planet's rising temperature. Creating such a shade would require 22 billion pounds (10 billion kilograms) of dust per year, which is "roughly 100 times more mass than humans have sent into space to date," the authors wrote in their study. The researchers say their study only evaluates the potential impact of this approach, as it could be "an option in addressing climate change if what we need is more time," Bromley said in a different statement(opens in new tab). The logistical, legal and technological challenges of implementing such an effort are not touched upon in the study. The team analyzed the sizes, shapes and compositions of different particles like coal dust, porous glass, sea salt and moon dust. They also compared the effectiveness of launching dust from a platform in space to blasting it from the moon's surface. Once placed at or near the first Lagrangian Point, or L1 — a gravitationally stable spot between the sun and Earth, about 1 million miles (1.5 million km) from our planet — the team used computer simulations to study how long these particles would hover. For example, in their modeling work, researchers launched a test particle from the moon's northern pole to an orbit close to L1. They found that the particle, launched at 1.7 miles per second (2.8 km per second), spent a total of five days in front of the sun before being dispersed.