Researchers have identified and measured a pollution plume following the breakup of a Falcon 9 rocket stage in the upper atmosphere (approximately 80–110 km) after an uncontrolled reentry in February 2025—and warn that commercial space activity is expanding faster than emissions monitoring and climate and ozone risks.
"It's just never been done before.,” said Robin Wing, a researcher at the Leibniz Institute for Atmospheric Physics in Germany, about the attempt to measure in real time the pollution created when space debris “burns up” on its way back to Earth. (Space) This week, his team presented first-of-its-kind proof that it is possible not only to see the fireball in the sky—but also to detect the “chemical fingerprint” it leaves behind.
The study, published on 2-19-2026 in the journal Communications Earth & Environment, analyzed an uncontrolled reentry event of a Falcon 9 rocket upper stage, which broke up on the night of February 19-20, 2025, over northern Europe. Using a ground-based LIDAR system that tunes for the resonances of certain elements, the researchers detected an unusual jump in lithium concentrations at an altitude of about 96 km—a level that allowed both high-resolution observation and the use of atmospheric models to attribute the plume to the reentry event itself.
What exactly is being measured, and why does it matter?
The region where the plume was measured—about 80 to 110 kilometers above the ground—is sometimes called the “forgotten zone” of the atmosphere, because until recent years it had almost no significant industrial impact, and it is relatively difficult to measure processes there using routine methods. According to the researchers, this is the first time that space debris from a defined reentry event has been “captured” by direct chemical measurement in this region, rather than just inferred indirectly.
Lithium, which appears in various components (including batteries) in spacecraft and rockets, serves as a convenient marker here: If lithium can be identified and the path of air masses can be traced back, a monitoring infrastructure can be built that can distinguish between natural contributions (e.g. from meteors) and anthropogenic contributions—man-made contributions. Wing noted that the next goal is to expand the measurements to other elements commonly found in spacecraft, to assess “how much and what” exactly is being injected into the upper atmosphere.
What is the connection between the climate crisis and the ozone layer?
The big story is pace. The number of launches and satellites is increasing, and so is the number of reentry events (controlled and uncontrolled) of satellites and rocket parts. This is where climate models come in, signaling the potential for cumulative impact: A study led by scientists at NOAA, which simulated a scenario of annual emissions of 10 gigagrams (10,000 tons) of aluminum oxide (Al₂O₃) particles from space debris returns by 2040, found that the particles could warm parts of the upper atmosphere by about 1.5 degrees Celsius and alter dynamic and chemical processes—including those that later affect the ozone layer.
The numbers in these scenarios are not based on “one satellite,” but on a world of giant constellations: estimates mentioned in scientific discussions speak of up to 60,000 satellites in orbit by 2040, with reentry into the atmosphere every day or two—a rate that could inject large amounts of metallic powders and aerosols into the upper layers.
At the 2025 European Geophysical Union (EGU) conference, concerns were also raised about other sources of pollution: for example, black carbon and components derived from certain fuels, which could affect both the radiation balance and ozone chemistry. The central idea that recurs in the discussions is that these emissions are injected “directly” into the layers that regulate climate and protect against radiation—and therefore their impact may be disproportionate to the amount of material.
And the regulation? A “shared environment” without systematic oversight
There are already international frameworks that define the responsibility of states for space activities—even when they are carried out by private companies. The Outer Space Treaty (1967) requires states to act “with due care” and avoid harmful contamination, and it also explicitly states the need to avoid adverse changes in the Earth’s environment. The Liability Convention (1972) adds principles of liability and compensation for damage caused by “space objects”—mainly with regard to damage to the ground or to aircraft. (unoosa.org)
But in fact, the measurement now presented highlights a gap: emissions in the upper layers of the atmosphere are distributed globally, and they also affect countries that have no launch industry at all. This means that without agreed monitoring and data transparency, it is difficult to even formulate standards—let alone enforce them. A UNEP report from the end of 2025 already warned that the rapid growth of the space sector is creating environmental challenges “in all layers of the atmosphere,” including air pollution from launch and reentry emissions. (UNEP – UN Environment Programme)
For Israel—which benefits from space infrastructure (observation and communication satellites, space-based services) but is not a “launch power” on the scale of the US or China—this is a clear example of the question of global environmental justice: who uses a common resource, and who bears the costs when impacts are dispersed into the air of all of us.
Suggested photo captions:
- Falcon 9 debris burns up in the sky over Europe (February 2025) — an event that became the first to be linked to a direct chemical measurement of a contaminant in the upper atmosphere. Credit: Bennett Theile / Space.com. (Space)
- Lidar beam for atmospheric measurements: A technique that allows for the identification of elements at altitudes of tens to hundreds of kilometers. (Illustration/example of Lidar systems).
- Atmospheric layers: The area where the plume was measured is above the stratosphere, in a range where processes also indirectly affect ozone chemistry and the radiation balance. Credit: NOAA.
For the full article atInside Climate News
More of the topic in Hayadan:
