A new report looks at the yearly reentry of large numbers of satellite constellations, noting that they can pose a significant hazard to people, both on the ground and in aircraft.

But how great are the risks we face?

The assessment — Large Constellation Disposal Hazards – has been authored by William Ailor of The Aerospace Corporation and issued by the group’s Center for Space Policy and Strategy. Ailor is a Technical Fellow with the Center for Orbital and Reentry Debris Studies at The Aerospace Corporation in El Segundo, California.

Random reentries

This first-order appraisal of potential risks to people and aircraft from random reentries of large numbers of satellites from large constellations in low Earth orbits shows that risks to aircraft posed by small debris surviving a reentry might be a major problem facing owners of large constellations, with worldwide risk of an aircraft striking a reentering debris fragment on the order of once every 200 years.

One object that survived reentry of an Iridium satellite has been discovered on the ground. Debris hat survived reentry of Iridium satellite on October 11, 2018.
(Photo courtesy Kings County Sheriff’s Office)

Furthermore, the report explains that hazards to people on the ground from larger debris objects will also be a significant problem, with expectations as high as one casualty every 10 years.

Debris survival

Credit: The Aerospace Corporation/Center for Space Policy and Strategy

The report adds that spacecraft components and features could be designed to have fewer large and small fragments survive, but only limited hard data on actual debris survival currently exists.


Given that hundreds of satellites per year from very large constellations could reenter, designers might find it difficult to eliminate many small fragments hazardous to aircraft and to verify whether proposed mitigation techniques perform as desired.



For a copy of this informative report, go to:


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