California start-up Make Sunsets is selling “cooling credits” for as little as $1, promising to dim the sun slightly by releasing sulfur dioxide into the stratosphere, a tactic known as solar geoengineering. Founder Luke Iseman and his customers hope the particles will block sunlight and cool the planet, though the approach is controversial and unregulated, with potential risks to global weather and health.
Competitor Stardust is developing a more sophisticated particle-based method, emphasizing safety and government oversight. Critics argue private companies should not wield such power over the climate, while proponents claim entrepreneurial agility could advance technology faster than traditional scientific efforts. As Iseman admits, “Whether you love us or hate us, we’ve let the genie out of the bottle in some small way.”