Blueshift outlines thermal plan for orbital data centres

Blueshift has outlined a three-part thermal management approach for spacecraft in low Earth orbit, aimed at vehicles ranging from satellites to orbital data centres.

The framework focuses on moving internally generated heat to radiators and rejecting it at the highest practical temperature, controlling heat flow within the spacecraft, and managing solar, Earth and environmental exposure at the surface.

The announcement comes as heat management receives more attention in low Earth orbit, where spacecraft repeatedly move between sunlight and shadow and where more computing-intensive payloads are under consideration. Blueshift said some high-power orbital computing concepts involve payloads above 100kW, increasing the importance of thermal design.

Low Earth orbit spacecraft can face temperature swings from -180°C to +150°C as lighting conditions change, with the cycle repeating 16 times a day. Those external shifts sit alongside internal heat loads from onboard systems, creating competing demands for designers trying to protect sensitive components while shedding waste heat.

Blueshift presents thermal protection as part of the wider spacecraft system rather than a separate material choice. The first element focuses on moving heat away from electronics and into radiators efficiently. The second aims to limit unwanted heat transfer inside the vehicle. The third addresses the effects of solar radiation and other environmental exposure on external surfaces.

The company said the first priority becomes more significant as onboard power requirements rise. In orbital data centre concepts, where processors would generate much larger heat loads than conventional payloads, the ability to reject heat at higher temperatures can affect radiator size and overall spacecraft design.

As part of that case, Blueshift pointed to its low Earth orbit track record, saying more than 20,000 square feet of its AeroZero Thermal Protection Systems are already flying in orbit. It also cited material testing and standards references including ASTM E595 and NASA-STD-6016.

Material data

Blueshift said AeroZero is used as a thermal break at brackets, joints and other interfaces, helping to isolate batteries and other temperature-sensitive systems from hotter electronics and coolant loops. In that arrangement, higher-powered processors can determine loop temperature, allowing radiators to run hotter and reject more heat per unit area.

According to the company, separating hot and cold zones can reduce radiator area and support smaller thermal systems. It presented this as one way to manage increasing heat loads without expanding spacecraft size to accommodate larger heat rejection surfaces.

In vacuum testing, Blueshift said AeroZero Thermal Protection Systems showed 19 times lower thermal conductivity and six times lower thermal diffusivity than standard polyimide tape. It said thermal diffusivity affects how quickly temperature changes move through a thermal break, which matters in an orbital environment where conditions can shift every 90 minutes.

The company also cited a modelled low Earth orbit comparison involving a solar cell on a composite frame in sunlight. In that scenario, the solar cell ran almost 40°C cooler with AeroZero Thermal Protection Systems than with standard tape, Blueshift said.

For exterior spacecraft surfaces, Blueshift said AeroZero Thermal Protection Systems has a solar absorptance-emittance ratio of 0.14, compared with 0.60 for uncoated Kapton. In illustrative steady-state calculations for a flat surface facing the Sun, it estimated a surface temperature of -32°C for AeroZero Thermal Protection Systems and +73°C for Kapton.

Design driver

Blueshift Co-Founder and President Tim Burbey said rising computing intensity is changing how engineers approach the issue.

"Every spacecraft produces internal heat, and now we are seeing data centers produce 100 times more, forcing it to become a design driver," said Tim Burbey, Co-Founder and President, Blueshift.

That position reflects a broader shift in the commercial space sector, where spacecraft proposals increasingly extend beyond communications and observation into computing and data processing roles. In those cases, thermal control can influence component layout, structural interfaces and the amount of radiator surface a spacecraft must carry.

Blueshift said it sees long-duration missions and harsher operating demands shaping the market for thermal materials. "Supporting reliable, long-duration missions in increasingly demanding orbital environments is a key focus for Blueshift," said Burbey.