The Case For Data Centers In Space

Video summary

Starcloud CEO Philip Johnston explains how an H100 reached orbit and why 88,000 satellites could host space-based AI data centers.

Starcloud co-founder and CEO Philip Johnston traces the idea to falling launch costs and a 2023 visit to SpaceX’s Starbase. After finding that space-based solar loses 95% of its power in transmission, the company pivoted to putting data centers in orbit, where Johnston estimates launch costs could break even at $500 per kilogram. Founded on January 1, 2024, Starcloud booked a SpaceX rideshare the next day. Its Starcloud-1 launched an Nvidia H100, tested AI workloads, and survived a two-week commissioning period that included troubleshooting a satellite that restarted every two hours. Johnston says the toughest engineering challenges are removing heat in a vacuum and protecting chips from radiation; Starcloud is developing lightweight radiators and testing commercial components. The planned 200-kW Starcloud-3 could enable 20 GW of compute across a proposed 88,000-satellite constellation. The company has won four government contracts and plans to serve military and satellite-imagery customers before scaling for hyperscalers as launch costs fall.

Chapters

1. 0:00Book a launch first: Starcloud reserved a SpaceX rideshare on January 2, 2024
2. 1:35The Starbase trip that started it: factories planned for three Starships per day
3. 3:20Why space-based solar didn't work: 95% transmission loss and a $500-per-kilo data-center threshold
4. 7:15First contact after 12 hours, then a restart fault that took three days to isolate
5. 9:42The two hardest problems: removing heat in vacuum and protecting chips from radiation
6. 11:27GPU radiation tests: 24 hours at accelerators simulates a five-year mission
7. 12:49Automotive-style components instead of expensive space-grade electronics
8. 14:30What 100 VCs got wrong: an H100 could run in orbit with phase-change cooling
9. 18:38The path to 20 GW in space: an FCC filing for 88,000 Starcloud-3 satellites
10. 21:16Designing a GPU for space with NVIDIA: Rubin chip work and a modified H100
11. 24:00Why hard tech became popular with VCs after Starcloud faced 100 rejections
12. 25:37Inside the Benchmark round: Chethan backed Starcloud’s engineering team
13. 26:57Their hiring strategy: 20 engineers, with a six-month wait for the first hire
14. 28:08How to be contrarian but right: recruit space engineers before choosing an idea
15. 31:44What if data centers get banned on Earth? New York blocks construction
16. 32:45Data center myth busting: water use, natural gas, and national security
17. 35:09Advice for hard tech founders: build the technical team first