By James Werner | 2025-03-06

On November 4, 2022, the worlds of aviation and space looked to the skies and waited for possible danger to fall over southern Europe, while thousands of travelers in France and Spain waited at the airport for their disrupted flights to be rescheduled.

As chance would have it, the Chinese-made 20-ton Long March 5B rocket body reentered the atmosphere over the Pacific Ocean.

As the rocket body uncontrollably returned back to Earth, it largely burned up, with some debris falling into the south-central Pacific Ocean, the US Space Command said at the time.

After the initial chaos settled, real economic and logistical consequences reverberated far beyond the flight cancellations and airport chaos.

More than two years later, many of the issues associated with this event remain, as does a staggering lack of public awareness.

Pocketbook pain

Although this was not the first time an abandoned rocket body reentered uncontrollably, it was the first time that national officials sounded the alarm on travel activity, pausing many flights and redirecting others.

It is estimated that these precautionary measures cost up to tens of millions of dollars, according to the International Association for the Advancement of Space Safety (IAASS).

The aviation industry and passengers bore the brunt of these costs, yet this event, along with past space debris return events, was caused by the space companies themselves.

At present, many space firms opt not to retrieve rocket bodies as a cost-saving measure, allowing them to reenter uncontrollably.

More than 2,300 rocket bodies remain in orbit, many of which are abandoned without consideration for future risk, according to research published on January 23 by Scientific Reports.

"This situation puts national authorities in a dilemma -- to close airspace or not -- with safety and economic implications either way," the report said. "Airspace authorities will face the challenge of uncontrolled reentries for decades to come."

While launch states are liable for damage caused by reentering space objects under international and domestic laws, it is less clear if they can be held liable for the economic costs caused by precautionary airspace closures, researchers said in a study published in Acta Astronautica last September.

What about the people?

In the scientific world, consequence is often measured with statistics and hard data. In many cases, this practice leads to a disconnect between the data and the effects on humans themselves.

The damage caused by a collision between an aircraft and even a small piece of space debris could be catastrophic, leading to the loss of an aircraft and potentially of hundreds of lives.

A mass greater than just 300 grams could result in total aircraft loss, especially if it hits critical structures or is ingested into an engine, the Range Commanders Council found in a November 2023 study.

The risks of failing to address space debris are not just theoretical.

The highest-density regions around major airports have a 0.8% chance per year of being affected by an uncontrolled reentry, according to the January 23 Scientific Reports study.

That rate rises to 26% in more densely populated regions such as the northeastern United States, northern Europe or major cities in the Asia-Pacific region.

The current approach to space debris -- largely one of neglect and passive monitoring -- presents a serious threat to aviation safety.

Busy skies, busy space

Space exploration and satellite deployment are continuing to rise, with ScienceDirect stating that the number of rocket launches grew from 87 in 2015 to 212 in 2023.

This growth, alongside a steady increase in air travel generally at the global level, has many observers worried about the risks associated with uncontrolled space debris -- particularly in the context of aviation safety.

While no verified collision between aircraft and space debris has occurred, instances of damage to aircraft from unidentified objects at cruising altitudes have been documented, according to the IAASS.

The risk is real, and the lack of a coordinated global solution is, although slowly, becoming more apparent.

Multilateral efforts are required to create controlled reentry policies that ensure all space debris safely returns to Earth, particularly over unpopulated areas like the ocean.

Efforts to fix it

As true for many issues on Earth, space safety can be improved with a concerted effort in informing the public and conducting effective policy.

Multilateral solutions to create a controlled reentry such as developing prediction capabilities for reentering space debris that cannot be controlled and adopting a protocol for precautionary safety warnings and airspace closures can be pursued as outlined by the 2023 Montreal Recommendations on Aviation Safety and Uncontrolled Space Object Reentries.

"Fortunately, uncontrolled reentries of rocket bodies are no longer necessary in most circumstances, due to technological developments and improved mission designs," the document says. "Uncontrolled reentries of satellites are not yet generally avoidable; however, steps can be taken to reduce reentry risks."

It outlines several recommendations for improving safety and the sustainability of space use, including establishing a new international body or building upon an existing one to provide a focus on the safety implications of uncontrolled reentries.

Space and Earth will be safer with coordinated action and international collaboration to prevent catastrophic events that could result from neglected space debris, the signatories to the recommendations urge.