By manufacturing thin-film bubbles in outer space, researchers want to shade the Sun’s rays from Earth.
A raft of thin-film silicon bubbles deployed from Earth into outer space and stretching to the size of Brazil could potentially block the Sun’s solar radiation from further warming Earth, possibly helping to not only stave off climate change, but potentially reverse it.
This new “space bubbles” plan offered by scientists at the Massachusetts Institute of Technology rifts off a concept first offered by astronomer Roger Angel. The multidisciplinary team of architects, civil and mechanical engineers, physicists and material scientists have worked on the technical and social aspects of what the group calls a “planetary-scale project” in an effort to find a non-Earth-bound solution to climate change.
The MIT group believes that if the raft of bubbles can deflect 1.8 percent of incident solar radiation before it hits Earth, they can fully reverse today’s global warming. Even if they can’t establish a 1.8 percent shading, they trust a smaller percentage provides enough benefit to help mitigate global warming.
To make it happen, the group proposes deploying small, inflatable bubbles into outer space that they could then manufacture into a space raft the size of Brazil and suspend near the L1 Lagrangian Point, the location between the Earth and Sun where the gravitational influence of both bodies cancel out. The team does suggest having some sort of system to ensure the raft stays in place and that may provide the ability to move the bubbles closer to the Sun for optimal impact.
“Unlike other Earth-based geoengineering efforts, such as dissolving gases in the stratosphere for increasing its albedo effect, this method would not interfere directly with our biosphere and therefore would pose less risks to alter our already fragile ecosystems,” the group says in a statement.
MIT cautions they don’t view the project as a replacement to current adaption and mitigation efforts, but as a backup solution should climate change spin out of control.
The team worked together to identify the best materials for the bubbles to withstand outer space conditions and how to deploy it. They also wanted to ensure they could fully reverse the implementation, something that can’t be done with previous aerosol proposals.
With silicon the leading material of choice for the shell of the thin-film bubbles, MIT researchers tested it in outer space-like conditions at a pressure of .0028 atm and at -50 degrees Celsius. They plan to investigate low vapor-pressure materials to rapidly inflate and assemble the rafts, whether with a silicon-based melt or a graphene-reinforced ionic liquid. There’s also further investigation needed to determine the ideal shell thickness.
MIT hopes engineers can craft a rapid-inflation production unit to create the frozen bubbles in the challenging environment of space. The team also believes a bit of science fiction may help in finding “novel ways” of shipping the material to space, such as a magnetic accelerator, known as a railgun.
“We believe that advancing feasibility studies of a solar shield to the next level,” Carlo Rattio, MIT Senseable City Lab professor, says in a statement, “could help us make more informed decisions in the years to come should geoengineering approaches become urgent.”