Publications Preprint · Orbital computing · 2026

Ungrounded Computing in Low-Earth Orbit: A Sustainability Audit

Juan A. Fraire, Robin Ohs, Gregory F. Stock, Andreas Schmidt, and Holger Hermanns

HAL preprint, 2026

Abstract

Orbital data centers are marketed as the sustainable answer to the energy, water, and land that terrestrial AI consumes. Constellations of computing satellites have been filed and demonstrators already fly, yet none of the filings we reviewed reports a lifecycle carbon assessment. This article runs the numbers the pitch leaves out. Using our lifecycle models, we audit the promises in three acts: the carbon of getting there (with launch and re-entry, orbital electricity is 1.5 to 2 times as carbon-intensive as terrestrial solar), the mass of staying alive (the radiator outweighs the GPU it cools three to twelve times over), and the price of never repairing (guaranteeing a sealed node’s survival adds 77–86% to its lifecycle carbon). Sustainability turns out to be a region of the design space, possibly an empty one, and we outline the research agenda needed to map it before these ungrounded ambitions leave the ground.

Cite

BibTeX

@article{fraire2026ungrounded,
  author  = {Fraire, Juan A. and Ohs, Robin and Stock, Gregory F. and Schmidt, Andreas and Hermanns, Holger},
  title   = {Ungrounded Computing in Low-Earth Orbit: A Sustainability Audit},
  journal = {HAL preprint},
  year    = {2026},
  url     = {https://hal.science/hal-05849193}
}

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