Space Bubbles: The Future of Environmental Sustainability?

As climbing temperatures and rising sea levels loom over humanity’s future, climate scientists, sustainability advocates, and environmental policymakers race to find a solution to climate change. Recently, some scientists have turned their attention away from reducing emissions and toward a far more peculiar method of stopping environmental catastrophe: blocking the sun.

It’s called solar geoengineering, the science of reflecting solar radiation away from the Earth back out into space, and thereby reducing the amount of heat trapped in Earth’s atmosphere. So what does this have to do with the pretty, little iridescent spheres we call bubbles? Well, MIT climate scientists have begun researching a solution to global warming through the solar geoengineering lens — using bubbles.

Yes, that’s right, bubbles. 

The idea of a space-based solar shield isn’t new. Building on the work of James T. Early, British-born American astronomer Roger Angel of the University of Arizona proposed in 2006 to use a transparent screen of megalithic size to reflect incoming sunlight away from Earth. 

In his research, Angel suggested this could be feasible with three scientific advancements. The first is the successful design of a thin refractive screen that could lead to a total sunshade of around twenty million tons. The second is a new method of space transportation using electromagnetic acceleration to escape Earth’s gravitational pull, followed up by ion propulsion to reduce the cost of such a project. Angel’s third idea was a network of “meter-sized ‘flyers,’” spacecraft acting a megastructural cloud, which could be stabilized autonomously by modulating the sun's radiation pressure. The flyers would act as transparent lenses or films that together would form a massive sunshade to deflect sunlight. 

Although this may sound like a lengthy and complex process, the payoff would be well worth it. Early and other climate researchers have estimated that a reduction of a mere 1.8% of solar radiation could reverse today’s global warming.

Of course, Angel’s plan would have to overcome major obstacles. Building such an apparatus to transport large masses of material out of the Earth’s atmosphere would be quite costly. It would also require significant energy to efficiently reach escape velocity. In addition, programming a network in which such a large amount of spacecraft could cohesively interact would be difficult. Finally, accounting for the wide variety of possibilities in outer space conditions is a complicated process. 

However, these challenges have not stopped the world’s top climate researchers from investigating this potential solution to impending climate destruction. Researchers at Massachusetts Institute of Technology’s (MIT) Senseable City Lab have recently begun working on Angel’s proposition but with a twist: They envision using a raft — about the size of Brazil — of small, inflatable frozen “space bubbles.” 

Essentially, the Earth could obtain a Banana Boat astronomical protective barrier that could allow the planet to safely tan for a while longer. 

Through experimentation and careful simulation, MIT’s researchers have tested bubbles in outer space conditions, developing a “stable solid thin-film spherical shell” in a vacuum chamber. Only 500 nm thick, the bubble was able to withstand a temperature of -50 degrees Celsius and a pressure of 0.0028atm. As the lab’s scientists continue their research, they are examining material, mass, cost efficiency, fabrication in space, and public policy. 

A major bonus of the bubble idea is that the solution would be fully reversible: The bubbles can be intentionally destroyed by breaking their surface equilibrium with limited space debris. 

Although it is still in the early stages of development, MIT’s researchers see potential in the idea. Given what’s at stake, the scientists say they must think outside the box. 

As MIT explains on the lab’s website, “Together, we can think radically to solve the worst case scenario.”