# Stratospheric Mirrors from Aerosol Injections: Make Sunsets' Approach to Cooling Earth

- Show: [Hardware to Save a Planet](https://hardwarepodcasts.com/podcast/hardware-to-save-a-planet)
- Published: 2025-03-13
- Length: 57m
- Episode: 74
- Page: https://hardwarepodcasts.com/podcast/hardware-to-save-a-planet/2025-03-13-stratospheric-mirrors-from-aerosol-injections-make-sunsets-approach-to-cooling-e
- Listen: https://podcasts.fame.so/e/2861kv7n-stratospheric-mirrors-with-aerosol-injections-luke-iseman

## Summary

Luke Iseman, founder of Make Sunsets, explains his company's approach to stratospheric aerosol injection by launching biodegradable balloons filled with sulfur dioxide to reflect sunlight and cool the planet. He details the hardware challenges of recovering payloads from the stratosphere, the unit economics of selling 'cooling credits' to individuals, and the ethical debates surrounding solar geoengineering. Iseman argues that immediate, scalable cooling is necessary alongside long-term decarbonization efforts, citing the low cost and high leverage of his current balloon-based MVP compared to academic proposals for aircraft fleets.

## Chapters

- [0:38](https://hardwarepodcasts.com/podcast/hardware-to-save-a-planet/2025-03-13-stratospheric-mirrors-from-aerosol-injections-make-sunsets-approach-to-cooling-e#t=38) Introduction and Guest Background
- [8:31](https://hardwarepodcasts.com/podcast/hardware-to-save-a-planet/2025-03-13-stratospheric-mirrors-from-aerosol-injections-make-sunsets-approach-to-cooling-e#t=511) The Make Sunsets Mission and Balloon Mechanics
- [13:54](https://hardwarepodcasts.com/podcast/hardware-to-save-a-planet/2025-03-13-stratospheric-mirrors-from-aerosol-injections-make-sunsets-approach-to-cooling-e#t=834) Ethical Debates and Perverse Incentives
- [17:30](https://hardwarepodcasts.com/podcast/hardware-to-save-a-planet/2025-03-13-stratospheric-mirrors-from-aerosol-injections-make-sunsets-approach-to-cooling-e#t=1050) Comparison to Carbon Removal and Climate Strategy
- [33:18](https://hardwarepodcasts.com/podcast/hardware-to-save-a-planet/2025-03-13-stratospheric-mirrors-from-aerosol-injections-make-sunsets-approach-to-cooling-e#t=1998) Hardware Challenges: Stratospheric Recovery and Radiation
- [41:11](https://hardwarepodcasts.com/podcast/hardware-to-save-a-planet/2025-03-13-stratospheric-mirrors-from-aerosol-injections-make-sunsets-approach-to-cooling-e#t=2471) Unit Economics and Scaling to Half a Degree Cooling

## Topics

- [Energy & climate tech](https://hardwarepodcasts.com/topic/energy-and-climate-tech)
- [Prototyping & iteration](https://hardwarepodcasts.com/topic/prototyping)
- [Pricing, margins & unit economics](https://hardwarepodcasts.com/topic/pricing-and-unit-economics)
- [Direct-to-consumer & e-commerce](https://hardwarepodcasts.com/topic/direct-to-consumer)

## Most relevant to

early-stage companies

## Mentioned

- Make Sunsets (company)
- YC (company)
- Mount Pinatubo (other)
- Project Loon (company)
- NASA (company)
- Stop Oil (company)

## Related episodes from other shows

- [The Carbon Copy: A rogue geoengineering startup sparks worry](https://hardwarepodcasts.com/podcast/catalyst/2023-04-27-the-carbon-copy-a-rogue-geoengineering-startup-sparks-worry) (Catalyst)
- [Making sense of solar engineering](https://hardwarepodcasts.com/podcast/catalyst/2022-06-16-making-sense-of-solar-engineering) (Catalyst)
- [Inside the most sophisticated plan for solar geoengineering](https://hardwarepodcasts.com/podcast/catalyst/2026-07-01-inside-the-most-sophisticated-plan-for-solar-geoengineering) (Catalyst)
- [Solange Massa (CEO/Founder, Ecoatoms)](https://hardwarepodcasts.com/podcast/just-gonna-send-it/2026-01-07-solange-massa-ceo-founder-ecoatoms) (Just Gonna Send It)
- [ICYMI... HIBT Lab! Climeworks: Jan Wurzbacher](https://hardwarepodcasts.com/podcast/how-i-built-this/2023-03-30-icymi-hibt-lab-climeworks-jan-wurzbacher) (How I Built This)

## Citing this page

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