Constellations of satellites, which are useful for providing access to high-speed internet, are also posing a threat to the environment due to the number of rockets required to deploy them. A new study reveals that their carbon footprint is nearly 100 times higher than the current bandwidth requirements.
The promise of internet access for everyone, anytime and anywhere, without the need for miles of cables, is what satellite constellation operators like Starlink, OneWeb, and Kuiper are selling. While they have technical arguments in their favor, many scientists are sounding the alarm about the damage they may cause or are already causing to the environment. These concerns include interfering with telescopic observations, emitting radiation, and contributing to the growing problem of space debris.
A study conducted by British and American researchers, published on the open server ArXiv, specifically focuses on the pollution caused by the rockets required to deploy these satellite constellations. Although the pollution caused by rockets is relatively insignificant compared to aviation, fewer rocket launches occur compared to flights. However, with the planned high number of satellites in these constellations, the pollution issue becomes significant.
The researchers analyzed the types of propellants used by the rockets planned for deployment in the three main constellations (Starlink, OneWeb, and Kuiper) to calculate the resulting pollution. They then estimated the carbon dioxide emissions per person based on the number of subscribers for each satellite operator.
The results, calculated over five years, showed emissions ranging from 0.7 to 3 tons for Kuiper, 1.41 to 1.7 tons for OneWeb, and 0.47 to 1.04 tons for Starlink. These figures are at least 30 times higher than the current internet network’s carbon footprint and up to 91 times higher according to the most pessimistic calculations.
However, due to uncertainties and unknown variables, the precise calculations remain somewhat imprecise. It is challenging to determine the exact number of subscribers for each satellite operator, let alone predict the number of subscribers in five or ten years. Therefore, the researchers relied on data provided by the industry.
Considering the current number of satellites and the planned future phases with even more satellites, the potential environmental pollution becomes a real concern.
The objective of providing global internet access may appear trivial compared to its environmental consequences. However, it is an important goal aligned with the United Nations’ Sustainable Development Goals. Edward Oughton, one of the study’s authors, emphasizes the need to find alternatives to limit the negative environmental impacts of future launches.
While satellite constellations are essential for achieving universal internet access, it is crucial to address the environmental concerns associated with their expansion. This could involve using less polluting rocket engines, launching more satellites in a single launch, or developing constellations that require fewer satellites to function properly. These considerations do not appear to be a priority for the operators at the moment.