Starcloud Trains First LLM in Orbit
Startup launched an Nvidia H100 GPU into orbit in November 2025 and trained the first large language model in space.
Y Combinator's official account posted that Philip Johnston, co-founder and CEO of Starcloud, launched an Nvidia H100 GPU into orbit in November 2025 and trained the first large language model in space. The same post states the company has since raised $200 million and reached a billion-dollar valuation. Harj Taggar retweeted a separate post from Johnston thanking the hosts of a podcast appearance. The Y Combinator post also links to a video and transcript on ycrootaccess.com without further detail supplied in the packet.
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,…
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6 postsYC 
Y Combinator@ycombinatorTune in: https://youtu.be/A9JDkiYEhfY Full transcript:
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PJ Philip Johnston@PhilipJohnstonThanks so much for having me on The Lightcone podcast @ycombinator, @garrytan, @snowmaker, @sdianahu and @harjtaggar! Such a fun discussion about the origins of @Starcloud_ and data centers in space! 🙏😃
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AO Alexis Ohanian 🗽@alexisohanianFantastic interview! Watch the whole thing, twice.
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PJ Philip Johnston@PhilipJohnstonThanks so much for having me on The Lightcone podcast @ycombinator, @garrytan, @snowmaker, @sdianahu and @harjtaggar! Such a fun discussion about the origins of @Starcloud_ and data centers in space! 🙏😃
- likes: 64
- replies: 5
- bookmarks: 10
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DI Diana@sdianahudatacenters in space sound incredible, but when you breakdown the eng, they seem less impossible than simply ambitious the tradeoff: the sun is a giant fusion reactor that already exists with free abundant energy but you pay for expensive transport + difficult cooling/comms
- likes: 125
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DI Diana@sdianahudatacenters in space sound incredible, but when you breakdown the eng, they seem less impossible than simply ambitious the tradeoff: the sun is a giant fusion reactor that already exists with free abundant energy but you pay for expensive transport + difficult cooling/comms
- likes: 125
- replies: 18
- bookmarks: 28
- reposts: 21
