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Kessler syndrome (orbital debris cascade)

Every collision in low Earth orbit makes fragments that can cause more collisions. Kessler and Cour-Palais described the risk in 1978. In 2009 two intact satellites collided for the first time. A runaway cascade would make some orbits unusable for years and take out services we rely on without noticing.

The tier rates the quality of the evidence, not how likely the event is.

How it could unfold

1. 1A collision or anti-satellite test creates a debris cloud● strong evidence
2. 2Fragments raise the collision rate for nearby satellites◐ moderate evidence
3. 3Loss of satellite services: navigation, weather, communications◐ moderate evidence

Historical anchors

• The 2009 collision of Iridium 33 and Cosmos 2251.

What you can do

• Do not rely on satellite navigation alone: carry a paper map and a compass for outdoor trips.

Open the preparedness checklist for this scenario →

Related scenarios

• Solar superstorm (Carrington-class)

References

1. Kessler, D.J. & Cour-Palais, B.G. (1978). Collision frequency of artificial satellites: the creation of a debris belt. J. Geophys. Res. 83:2637-2646. link ↗
2. NASA Orbital Debris Quarterly News, vol. 13 issue 2 (2009): the Iridium 33 / Cosmos 2251 collision. link ↗