Daily Brief — April 24: Nuclear and Ecash

NASA just moved nuclear spacecraft from concept to engineering schedule. On April 14, Administrator Jared Isaacman announced that SR-1 Freedom — a 20-kilowatt nuclear-electric propulsion craft — will launch in December 2028, with design completion starting June 2026 and final assembly between January and October 2028. The spacecraft will reuse power-and-propulsion hardware originally designed for the orbital Gateway station, now being deprioritized. Steve Sinacore, program executive of NASA's Space Reactor Office, laid out a two-phase roadmap: SR-1 serves as the proof-of-concept, then Lunar Reactor-1 in 2030 informs production-scale reactors reaching megawatt class in the 2030s. The first phase alone carries a $10 billion investment across 24 launches delivering 4,000 kg to the lunar surface, including VIPER rover, terrain vehicles, and orbital relays. This is the single most consequential space infrastructure story of the month.

Blue Energy raised $380 million on April 22 to build factory-scale nuclear reactors in shipyards and assemble them on-site for AI data centers and industrial users. The capital is flowing toward infrastructure powering the next wave of AI and energy systems — away from standalone software and toward platforms designed for massive real-world demand. The first 1.5 GW project launches in Texas. This signals a direct competition between shipyard-modular nuclear and long-duration energy storage (lithium-ion alternatives like flow batteries and sodium-ion) as the preferred power answer for large-scale AI operations. Two arXiv papers from this week are directly relevant: Almassalkhi et al. identified DER coordination gaps that distributed nuclear helps bridge, and Tönges et al. mapped the smart-metering infrastructure that Blue Energy's Texas project will require.

Fedimint shipped v0.11.0 and v0.11.1 within 24 hours on April 21. The headline feature is gateway recovery and mnemonic management for first-boot setup — closing a critical gap where losing a Fedimint gateway could strand user funds. This matters because gateways are the bridge between the Ecash mint layer and Lightning Network. The releases arrive alongside Core Lightning v26.04, which deployed negative routing fees for channel liquidity management. Together they reflect an ecosystem maturing toward operational robustness: the arXiv paper on differentially private federated learning (Xu et al., April 22) shows exactly the kind of privacy-preserving aggregation that Fedimint's architecture approximates at the protocol level.