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Comparison
Helium-3: Terrestrial vs Lunar
Earth's helium-3 is scarce; the moon's is abundant but far. Kronos sidesteps both by breeding its own helium-3 in the plasma.
- Terrestrial
- Scarce — from tritium decay; thin market
- Lunar
- Abundant in regolith; far and undeveloped
- Kronos source
- Bred in situ via catalyzed D–D
- Dependence
- Neither is required
Helium-3 supply is the classic objection to D–³He fusion, and the two natural sources both have problems.
| Source | Availability / status |
|---|---|
| Terrestrial ³He | Scarce — mainly from tritium decay; the open market is thin |
| Lunar regolith ³He | Abundant (billions of years of solar wind), but far away and undeveloped |
| In-situ breeding (Kronos) | The plant breeds much of its own via catalyzed D–D |
Kronos's answer is to depend on neither. By breeding helium-3 in the plasma, the plant supplies much of its own fuel, turning a scarcity problem into a fuel-cycle engineering problem. Lunar ³He remains a genuine long-horizon resource — a subject some Kronos advisors have studied for decades — but the commercial design works without ever leaving Earth. See where does helium-3 come from?