Starcloud is an American company developing orbital data centers: satellites that turn sunlight into electricity for onboard AI computing hardware. Founded in January 2024 under the name Lumen Orbit,[1] it is headquartered in Redmond, Washington.[2] Its first satellite, Starcloud-1, launched on a SpaceX Falcon 9 on November 2, 2025 and carried the first NVIDIA H100 data-center GPU to fly in space.[3][4] In December 2025 the spacecraft trained a small language model on board, the first AI model trained in orbit.[5][6]

The company raised about 200 million dollars in its first two years, reaching a 1.1 billion dollar valuation with a Series A round in March 2026,[7][8] and has asked the US Federal Communications Commission for permission to operate up to 88,000 satellites,[9] a constellation it says would eventually supply about 20 gigawatts of computing power.[10] Its case rests on near-continuous solar power and radiative cooling in orbit; independent analysts respond that radiator mass, launch prices, and launch emissions leave the economics unproven.[11][12]

History

Philip Johnston, Ezra Feilden, and Adi Oltean founded Lumen Orbit in January 2024 and took it through Y Combinator's summer 2024 batch.[1] Johnston, the chief executive, previously worked on satellite projects at McKinsey; Feilden, the chief technology officer, holds a PhD in materials engineering and worked on deployable solar arrays at Airbus Defence and Space and Oxford Space Systems; Oltean, the chief engineer, spent two decades at Microsoft and worked on Starlink beam software at SpaceX.[2] The startup raised a 2.4 million dollar pre-seed round led by Nebular in March 2024, then an oversubscribed seed round of more than 10 million dollars, reported that October as one of the largest from its Y Combinator cohort.[1]

In February 2025 the company renamed itself Starcloud, after Lumen Technologies asserted rights to the name "Lumen" for data centers, and disclosed another 10 million dollars that brought the seed total to 21 million.[13] At that stage NVIDIA's involvement ran through its Inception startup program, which supplied discounted chips rather than investment.[13][14] Starcloud now lists NVIDIA among its investors, alongside NFX, Y Combinator, IQT, Sequoia, Benchmark, Andreessen Horowitz, and EQT.[2] A 170 million dollar Series A, led by Benchmark and EQT Ventures and announced on March 30, 2026, valued the company at 1.1 billion dollars; at the same time Starcloud said it was preparing a 3,000-square-meter production facility in Woodinville, Washington.[7][8]

Starcloud-1

Starcloud-1 reached orbit on SpaceX's Bandwagon 4 rideshare mission from Cape Canaveral on November 2, 2025.[3][4] The 60-kilogram spacecraft, built on Astro Digital's Corvus-Micro bus, entered a roughly 325-kilometer orbit for a planned 11-month mission ending in a destructive reentry.[3] Its payload is an NVIDIA H100 GPU with 80 gigabytes of memory, which the company described as about 100 times more GPU computing power than had ever flown in space.[4][14] One early application is processing synthetic aperture radar imagery from Capella's satellites in orbit: "Downlinking SAR data has historically been a huge problem because it's extremely voluminous," Johnston said, whereas the satellite can send down a 1-kilobyte packet of results instead of hundreds of gigabytes of raw imagery.[4]

In December 2025 the satellite ran Google's open-source Gemma model and trained NanoGPT, Andrej Karpathy's small language model, on the complete works of Shakespeare, the first AI model trained in space.[5][6] Karpathy described the result as "the first LLM to train and inference in space."[6]

Starcloud-2 and the roadmap

The 450-kilogram Starcloud-2 is designed to generate about 8 kilowatts, roughly 100 times the power of Starcloud-1, and to carry the largest commercial deployable radiator yet flown.[8] Its payload includes multiple GPUs, among them an NVIDIA Blackwell chip and an Amazon Web Services server blade, and the mission has partnerships with NVIDIA, AWS, and Google Cloud.[7][8] Cloud provider Crusoe, the first customer, agreed in October 2025 to deploy its Crusoe Cloud service on the satellite, with launch planned for late 2026 and limited GPU capacity offered from space in early 2027.[15] Starcloud says the spacecraft will be fully operational in sun-synchronous orbit by 2027.[16] In May 2026 Johnston said the launch was about eight months away and that signed contracts would cover the mission's cost.[10]

The next step, Starcloud-3, is a three-ton, 200-kilowatt-class spacecraft sized for Starship, which could deploy about 50 of them per launch, roughly 10 megawatts at a time; Starcloud projects the design entering service in mid- to late 2028.[8]

The 88,000-satellite plan

Starcloud applied to the FCC on February 2, 2026 for a constellation of up to 88,000 satellites, and the commission accepted the application for processing on March 13.[9] The filing describes narrow orbital shells between 600 and 850 kilometers in sun-synchronous dusk-dawn orbits chosen for near-continuous solar power, satellites designed to demise fully on reentry, and optical links carrying traffic to broadband constellations including Starlink, Amazon's Project Kuiper, and the planned Tera Wave network.[9] The proposal is far larger than any constellation in service, though smaller than the up to one million compute satellites SpaceX has proposed[9] for Starmind, its own orbital data center constellation.

Johnston has said full deployment, equivalent to about 20 gigawatts of power, depends on Starship flying frequently and launch prices falling below roughly 500 dollars per kilogram, and would begin "probably 2029 or 2030."[10] The company's engineering work centers on deployable radiators it wants to build at a tenth the mass and a hundredth the cost of designs like those on the International Space Station, and on radiation tolerance, tested with cyclotron and heavy-ion beams.[10]

Rationale and skepticism

Starcloud's argument is that a data center in the right orbit receives almost uninterrupted sunlight without needing batteries and can reject waste heat to the vacuum of space by radiation, avoiding the land, energy grid, and permitting constraints of terrestrial sites.[2][14][15] The company projects energy costs about ten times lower than on the ground, with a similar claimed reduction in carbon emissions, and has sketched a 5-gigawatt orbital data center whose solar arrays and radiators would measure roughly 4 kilometers on a side.[14] "In 10 years, nearly all new data centers will be being built in outer space," Johnston said in 2025.[14]

Independent analyses are more cautious. An IEEE Spectrum assessment calculated that a single 700-watt H100 needs about 1.4 square meters of radiator and a 40-kilowatt AI rack about 80 square meters, that radiator coatings degrade enough within five years to require around 40 percent more area, and that radiators and solar arrays can account for 65 to 70 percent of a satellite's mass; even at an optimistic Starship price of 44 dollars per kilogram, it concluded, a GPU-year in orbit would cost at least ten times more than in a terrestrial data center.[11] Scientific American cited Saarland University researchers who found that, once launches and reentry pollution are counted, orbital data centers could produce an order of magnitude more emissions than terrestrial ones, and astronomer Samantha Lawler's warning that such plans would worsen space debris.[12]

References

  1. Lumen Orbit closed one of the biggest rounds from Y Combinator's last cohort - TechCrunch, October 24, 2024.
  2. Starcloud - Starcloud.
  3. Starcloud 1 (Lumen 1) - Gunter's Space Page.
  4. Nvidia Sends a Powerful GPU to Space - IEEE Spectrum, November 3, 2025.
  5. Starcloud plans its next moves after training first AI model in space - GeekWire, December 22, 2025.
  6. Starcloud-1 - Starcloud.
  7. Starcloud raises $170 million Series A to build data centers in space - TechCrunch, March 30, 2026.
  8. Starcloud achieves unicorn status with $170 million raise for orbital data centers - SpaceNews, March 30, 2026.
  9. Starcloud files plans for 88,000-satellite constellation - SpaceNews, March 15, 2026.
  10. Starcloud's path to 88,000 computing satellites - SpaceNews, May 27, 2026.
  11. Why Thermodynamics Rules Future Orbital Data Centers - IEEE Spectrum, June 11, 2026.
  12. Space-Based Data Centers Could Power AI with Solar Energy, at a Cost - Scientific American, December 9, 2025.
  13. Lumen Orbit changes its name to Starcloud and raises $10M for space data centers - GeekWire, February 26, 2025.
  14. How Starcloud Is Bringing Data Centers to Outer Space - NVIDIA Blog, October 15, 2025.
  15. Crusoe to Become First Cloud Operator in Space Through Strategic Partnership with Starcloud - Crusoe, October 22, 2025.
  16. Starcloud-2 - Starcloud.