SAN JOSE, Calif. — One morning late last year, an RV pulled into a parking lot on the outskirts of Silicon Valley. Inside it was a blue Ikea bag with huge balloons, and metal tanks full of helium and sulfur dioxide gas.
The mission was led by Luke Iseman, a 41-year-old serial entrepreneur with a mohawk hairstyle and an orange t-shirt that read "Cool Earth." Inspired by a science fiction novel, Iseman had founded a company in 2022 called Make Sunsets. In the novel, a billionaire undertakes a type of "solar geoengineering": shooting vast amounts of reflective particles high into the atmosphere to reflect sunlight off Earth and counter global warming. Now, Iseman was trying to do it in the real world.
