The Impact of Computing Data Centres Orbiting Earth

TL;DR

Placing large-scale computing data centers in low-Earth orbit could supply significant power but would cause substantial astronomical, technical, and cultural issues due to their brightness, visibility, and collision risks.

Contribution

This paper analyzes the technical feasibility and potential astronomical and cultural impacts of deploying large computing data centers in low-Earth orbit.

Findings

A 4x4 km solar array in orbit would be visible as a bright object comparable to the Moon.

Such structures would block celestial objects and increase collision risks in space.

Orbiting data centers could shine at magnitude -5 to -7, affecting astronomy and sky observation.

Abstract

Artificial intelligence is projected to increase U.S. data centre power demand beyond 100 gigawatt by 2035 and global demand toward 1 terrawatt. In response, companies and governments have proposed placing computing infrastructure in sun-synchronous low-Earth orbit, where continuous sunlight could supply electrical power. Generating 5 GW would require solar arrays 4 x 4 kilometers in size. Although technically feasible, such structures at roughly 500 km altitude would dramatically alter both the night and daytime sky. A 4 x 4 km array in low earth orbit would span about 0.4 degrees, comparable to the Moon, and reflected sunlight would make it shine at magnitude g = -5 to -7 mag, 100 times brighter than the brightest stars. Dozens of these structures would appear as a north-to-south chain of industrial objects across the sky, visible for about 1 1/2 hours after sunset and 1 1/2 hours before sunrise. They would block stars, planets, and deep-sky objects for minutes at a time, while increasing the likelihood of collisions that could trigger runaway debris production. These orbiting computing facilities therefore pose serious astronomical, technical, and cultural concerns.