Y Combinator@ycombinatorAug 5

Philip Johnston (@PhilipJohnston) is the co-founder and CEO of @Starcloud_, the company building data centers in space. In November 2025, Starcloud launched an Nvidia H100 GPU into orbit and trained the first large language model in space. They've since raised $200 million, hit a billion-dollar valuation just 17 months after YC demo day and filed with the FCC to deploy 88,000 more satellites. In this episode of @LightconePod, Philip walks us through their wild origin story, the engineering challenges behind the Starcloud-1, why they booked a SpaceX launch before they even knew what they were building and how data centers in space make sense both economically and politically. 00:39 — Why Build Data Centers in Space? 01:40 — The Insight That Started Starcloud 04:43 — Launching Starcloud-1 09:45 — The Engineering Behind Data Centers in Orbit 13:49 — Why 100 VCs Said No 16:12 — Book the Launch Before You Build the Product 18:32 — The Roadmap to Commercial Space Compute 21:10 — Building NVIDIA GPUs for Space 23:41 — Raising $170M for a Hard Tech Startup 26:37 — Hiring the World's Best Space Engineers 31:25 — Why AI Compute Is Moving to Space 34:49 — Advice for Hard Tech Founders