The “bubble” cluster floating above Earth to reflect sunlight could help reverse global warming.
Droughts, extreme heatwaves, and major wildfires are currently impacting the entire globe. Many cities around our planet have broken temperature records this summer. Despite international efforts to combat global warming, it seems that Earth may have reached a point of no return.
What will happen if we fail to keep temperature increases below +2⁰C? Scientists are exploring “last chance” solutions aimed at limiting damage or even reversing climate change.
Inspired by an idea proposed by astronomer Robert Angel, a team of researchers from the Massachusetts Institute of Technology (MIT) in the United States is currently investigating a concept for a solar shield, which would act as a barrier to reduce the amount of radiation hitting our planet.
The Space Bubbles research project, led by architect Carlo Ratti alongside other researchers at MIT, proposes creating a “raft” made of multiple frozen bubbles at the Lagrange Point L1, located between Earth and the Sun. The bubbles would be made from thin-film materials and produced in space. When connected, they would cover an area equivalent to that of Brazil (8.5 million km2).
When combined, the bubble raft will span the area of Brazil. (Photo: MIT)
Space Bubbles represent a variation of the idea of cooling Earth with a solar shield, functioning by blocking a portion of radiation from the star, thereby alleviating the effects of global warming. However, the key difference is that a space-based solar shield poses no risk to Earth’s biosphere. Projects implemented in the stratosphere carry this inherent risk.
The MIT research team emphasizes that Space Bubbles are designed to support efforts to mitigate the current climate change trend. “Geoengineering is our only option,” stated Ratti, head of MIT’s Senseable City Lab. “However, geoengineering proposals are all Earth-based, posing a massive risk to ecosystems. A space solution would be safer. For example, if we could deflect 1.8% of sunlight before it reaches Earth, we could completely reverse global warming.”
Another advantage of this type of solar shield is that the bubbles can deflate and be retrieved from their location. The spheres are made from materials such as silicon, transported into space in a molten state or as a liquid reinforced with graphene. The MIT team successfully conducted a preliminary experiment by inflating the shell of the sphere in outer space conditions. They believe this could be one of the most effective thin-film structures for deflecting sunlight.
The Space Bubbles research project was developed from the idea of scientist James Early, who first proposed deploying objects to deflect radiation at Lagrange points, and astronomer Roger Angel, who suggested the design of bubble rafts. The interdisciplinary research team hopes to demonstrate the feasibility of the project through further experiments and analyses. In addition to materials, the research will explore options for transporting materials from Earth, the location and stability of the bubble raft, cost-effectiveness, maintenance, and impacts on climate and ecosystems.
