---
type: claim
domain: space-development
description: "Lunar south pole operations require power during 14-day nights ruling out solar-only; NASA-DOE targeting 40 kWe fission reactor delivery to launch pad early 2030s with Westinghouse as prime"
confidence: likely
source: "Astra, web research compilation February 2026"
created: 2026-02-17
secondary_domains:
  - energy
depends_on:
- power is the binding constraint on all space operations because every capability from ISRU to manufacturing to life support is power-limited
related:
- Heat-based helium-3 extraction on the lunar surface faces a fundamental power-mobility dilemma that makes large-scale extraction impractical with current technology
reweave_edges:
- Heat-based helium-3 extraction on the lunar surface faces a fundamental power-mobility dilemma that makes large-scale extraction impractical with current technology|related|2026-04-17
sourced_from:
- inbox/archive/2026-02-17-astra-space-manufacturing-power.md
---

# Nuclear fission is the only viable continuous power source for lunar surface operations because solar fails during 14-day lunar nights

The lunar south pole -- where water ice deposits exist in permanently shadowed craters -- experiences 14-day periods of darkness. Solar power alone cannot sustain continuous operations through these nights, making nuclear fission a structural necessity rather than a preference. NASA and DOE are developing a Fission Surface Power system targeting 40 kWe (enough to continuously power 30 households for 10 years) in a package under 6 metric tons.

The technology heritage is strong. The KRUSTY experiment (Kilopower Reactor Using Stirling Technology) demonstrated successful operation under normal and off-normal conditions in 2018. Westinghouse was selected in January 2025 to continue space microreactor development. L3Harris is developing nuclear power and propulsion solutions for the Artemis program. The delivery target is a reactor at the launch pad in early 2030s, with a 1-year demonstration followed by 9 operational years on the Moon.

Next-generation RTGs for deep-space missions are also advancing: the NGRTG targets 242 We (more than double the current 110 We MMRTG), with a flight-ready manufacturing line by 2030. Trump's executive order on space superiority made lunar nuclear reactors and orbital nuclear power a priority. The trajectory is clear: nuclear power in space is moving from heritage deep-space missions to surface infrastructure.

## Evidence
- KRUSTY reactor demonstration (2018) — successful operation under all conditions
- Westinghouse selected January 2025 for space microreactor development
- NASA-DOE Fission Surface Power: 40 kWe target, <6 metric tons, early 2030s
- NGRTG: 242 We target, flight-ready manufacturing line by 2030

## Challenges
Regulatory and political challenges around launching nuclear material remain significant. Plutonium-238 supply constraints may limit RTG production. Fission reactor technology is mature but space-qualified systems require extensive testing.

---

Relevant Notes:
- [[power is the binding constraint on all space operations because every capability from ISRU to manufacturing to life support is power-limited]] — nuclear fission is the primary answer to the binding power constraint for lunar operations

Topics:
- [[space exploration and development]]