Satellite mega-constellations create risks in Low Earth Orbit, the atmosphere and on Earth

Area of Science:

• Space debris and atmospheric science
• Orbital mechanics and space governance

Background:

• The proliferation of large satellite constellations, often termed mega-constellations, presents novel environmental challenges.
• Current space asset management models, akin to consumer electronics, overlook crucial Earth-space environmental interconnections.

Purpose of the Study:

• To analyze the multifaceted risks associated with mega-constellations, including impacts on ground-based astronomy, orbital environments, and Earth's upper atmosphere.
• To highlight the inadequacy of existing regulatory frameworks in addressing the scale and nature of mega-constellation deployment.

Main Methods:

• Utilizing simple models to assess the atmospheric deposition of aluminum from satellite re-entries.
• Evaluating collision risks from untracked debris within densely populated mega-constellation orbital shells.
• Analyzing the increased probability of meteoroid impacts due to the expanded cross-section of satellites.

Main Results:

• Satellite re-entries, particularly from constellations like Starlink, could become a primary source of high-altitude alumina, potentially exceeding natural meteoroid contributions.
• Untracked debris and the sheer number of satellites significantly increase the likelihood of on-orbit collisions.
• The expanded satellite cross-section elevates the risk of impacts from meteoroids.

Conclusions:

• Mega-constellations risk 'tragedies of the commons' across multiple domains: astronomy, orbital space, and the atmosphere.
• Urgent international cooperation and a revised regulatory system are required to manage the environmental and safety implications of tens of thousands of satellites.