Two years ago, a Californian startup, Make Sunsets, pumped a few grams of sulfur dioxide into a series of weather balloons and launched them into the stratosphere.
Pro
Analysis
September 4, 2025
Dimming the sun, refreezing the ice: VCs flirt with geoengineering
Is there a venture case behind large-scale modification of the planet’s systems?
5 min read
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