Cowboy raises $275 million to build rockets with orbital data center upper stages

TAMPA, Fla. — Cowboy Space, founded less than two years ago as Aetherflux to develop space-based solar power, has raised $275 million at a $2 billion valuation to build rockets with upper stages that would serve as data centers once in low Earth orbit (LEO).

The San Carlos, California-based startup said early-stage investor Index Ventures led the Series B funding round in a brief May 11 news release, after leading its $50 million Series A last year.

Cowboy founder and CEO Baiju Bhatt, who also co-founded financial services app Robinhood and joined the funding round, told SpaceNews the venture has now raised around $365 million to date.

The deal makes Cowboy one of the space industry’s fastest “unicorns” — privately held companies valued at $1 billion or more — just over a month after two-year-old Starcloud crossed the threshold with a $170 million Series A to develop its own orbital data centers.

Starcloud is looking to raise at least $200 million more in a deal that would double that valuation to $2.2 billion, according to a source close to the situation, as SpaceX, Blue Origin and others also chase an emerging market promising to address the power and cooling constraints facing terrestrial data centers.

AI giant Anthropic underscored that demand last week when it expressed interest in using SpaceX’s proposed orbital data centers as part of a broader agreement for access to the company’s terrestrial compute capacity.

“Cowboy is building at exactly the right moment, as demand for AI compute and energy begins to outstrip what terrestrial infrastructure can support,” Index Ventures partner Jan Hammer said.

“Baiju has a proven track record of reimagining massive markets from first principles, and his lifelong passion for physics makes space the ultimate market opportunity for that ambition.”

The plans call for power and data center constellations numbering in the many thousands, potentially reaching tens of thousands of satellites.

With Cowboy having yet to deploy its first satellite, the funding underscores massive investor appetite for orbital data centers as the market becomes an increasingly prominent part of SpaceX’s growth story ahead of its potential IPO this summer.

Solar building block

Bhatt said it is too early to provide finer details on its ambitious plans for vertically integrated infrastructure spanning launch vehicles, space-based power and in-orbit compute.

While rivals such as Starcloud plan to rely on SpaceX’s Starship heavy-lift rocket, Cowboy says designing the rocket upper stage and data center payload as a single vehicle reduces redundant mass, optimizing the amount of power and compute delivered to orbit.

Its first space mission, planned for later this year, is a small satellite built in partnership with four-year-old manufacturer Apex to demonstrate wireless power beaming from LEO to the ground using infrared lasers.

Cowboy is still finalizing specifications for the power-beaming demonstration mission, which Bhatt described via email as “a subscale technology demonstrator” sized to prove the physics and validate the approach.

“It’s a building block, but the long-term business focus is on using that power in orbit for AI compute, not just beaming it to Earth,” he added.

Other startups are also looking at ways to supply more energy to spacecraft.

Florida-based Star Catcher, for instance, is developing an optical power-beaming constellation designed to transmit energy to satellites through their existing solar arrays.

Andrew Rush, Star Catcher cofounder and CEO, outlined how shared power infrastructure could improve the economics of orbital data centers during a recent SpaceNews event.

There is also growing interest in using space-based solar power for energy-hungry terrestrial data centers. Overview Energy, a Virginia-based venture that emerged from stealth last year, recently announced an agreement to provide up to one gigawatt of power from space for Meta’s terrestrial data centers as soon as 2030.

Brains in orbit

Early next year, Cowboy aims to deploy its first “Galactic Brain” data center node, using NVIDIA Space-1 Vera Rubin modules designed for AI computing in LEO.

Bhatt said the mission would mark the first step toward demonstrating orbital AI compute powered by solar energy, ahead of plans for its first proprietary rocket launch carrying a one-megawatt data center by the end of 2028.

“The orbital data centers are where the architecture gets interesting,” he said, as “each upper stage leverages the full mass and volume of the vehicle to package power generation, cooling, and compute together — including using the stage structure itself as a radiator.”

The hybrid rocket/satellite would be larger than SpaceX’s 70-meter-tall Falcon 9 but smaller than Starship, which stands at more than 120 meters, targeting 20,000-25,000 kilograms of payload capacity to orbit.

Design work is underway across multiple cities, with satellite engineering in Seattle and rocket engine development in Los Angeles.

The team includes former SpaceX director of launch operations Tyler Grinnell and Warren Lamont, who led rocket engine and booster stage development at Blue Origin.

“We’re building everything in-house,” Bhatt added. “At Cowboy, we’re designing the launch vehicle, upper stage, and orbital compute platform as a single integrated system optimized specifically for AI infrastructure in orbit. That level of integration requires full vertical control — we’re not relying on external providers for core architecture.”

While SpaceX has demonstrated the power of vertical integration with rockets and satellites, Cowboy aims to be the first to build a launch vehicle whose upper stage is designed from day one to become a data center in orbit.

It remains to be seen whether Cowboy follows SpaceX in returning parts of flown rockets for reuse.

“We’re designing for reusability where it makes economic sense, but the primary focus is on delivering maximum compute and power to orbit efficiently,” Baiju said.

“The architecture is optimized for mass efficiency and performance — not just reuse for its own sake.”

Cowboy did not disclose other details about how it plans to enter the notoriously challenging launch market, or build the cadence needed to sustain meaningful LEO operations.

Bhatt said the size of the power-beaming and computing constellations will be driven by the economics Cowboy seeks to validate through their upcoming technology demonstrations.

The startup has also not yet filed plans for the constellations with the Federal Communications Commission, beyond experimental license requests.

“Our focus is on demonstrating capability before scaling to full commercial services,” Bhatt said, adding: “Initial commercial services will follow once we’ve validated performance, reliability, and economics at scale.”

New investors IVP, Blossom Capital and SAIC also participated in the Series B, alongside existing backers Breakthrough Energy Ventures, Construct Capital, Andreessen Horowitz, NEA and Interlagos.