Climate Action
In Space, No One Can Hear The Pollution
October 28, 2025
When we hear people talk about “pollution,” we generally assume they’re talking about pollution on Earth. Slogans like “There is no Planet B,” “Go Green,” or “Save the Earth,” are meant to warn people that we only have one habitable planet, and we have to cut back on our waste and pollution and use renewable energy sources to keep it habitable. However, pollution exists off-world, too, and it’s a bigger deal for our Earth than you might think.
Space pollution refers to human-made debris outside of the Earth’s atmosphere. The European Space Agency estimates that, as of September 2025, there are 54,000 space debris objects greater than 10 cm. And a further 1.2 million greater than 1 cm to 10 cm, and another 140 million greater than 1 mm to 1 cm. It is mainly composed of satellite debris and stray parts, like chipped paint, broken metal, and construction materials.
In space, this pollution might not directly harm animals or ecosystems, but its impacts are more insidious.
Space Pollution Harms Modern Society
While these objects are not in Earth’s atmosphere, our planet’s gravitational pull compels them to stay close. They form a “belt” around our planet, moving at 17,500 miles per hour — about 10 times as fast as a bullet, so even the smallest pieces are extremely dangerous if they collide with anything.
This poses a significant risk to astronaut safety (though organizations like the ISS have developed shields and suits to protect their staff), and can severely damage satellites. This could trigger Kessler Syndrome, a chain reaction in which collisions cause debris, which causes more collisions, and so on.
Although satellites, like space debris, might seem abstract or distant, they are indispensable in the modern world. Governments use them to monitor climate and weather, as well as for vital military operations. Internet and television companies rely on satellites for strong Wi-Fi connections — which is why Amazon just launched its first internet satellites this April to compete with Elon Musk’s satellite-based internet company, Starlink.
If all our satellites suddenly stopped working, the systems we all depend on, like air traffic control, ATMs, the stock market, global Wi-Fi, the World Wide Web, and GPS would be severely damaged or cease to exist. This would put us back to 1950, in terms of technology, overnight.
Additionally, if space debris limits the kind of work scientists can do, because it makes space dangerous — we could lose out on future discoveries that might transform life on Earth for the better.
Satellites and Climate Change
For climate activists, satellites are important sources of data. Satellites can trace greenhouse gas emissions, track the diminishing polar ice caps, as well as broader land and sea temperature changes, and they detect underwater pollution, including coral bleaching. It would be nearly impossible to show people how the Earth is changing without images coming from space and, therefore, far more difficult to inspire the urgency needed to save our only home. This is also why the Trump administration wants to destroy two satellites that act as Orbiting Carbon Observatories– without them, it’d be a lot more difficult to show people how climate change threatens our future.
For us down here on Earth, we are really not aware of this growing problem … and we are really not able to connect to it. Unless we make that human connection, it’s not something we would be able to address.
Hugh Lewis, Professor of Astronautics
Space Pollution Doesn’t Stay Put
Another grave problem is that space pollution doesn’t stay in space forever. On March 8th, 2024, a family in Florida sued the National Aeronautics and Space Administration (NASA) $80,000 because a piece of space debris, from a cargo pallet they owned, struck their house and damaged their roof and floor. Likewise, in early 2025, The New York Times reported that a village in Kenya was struck by a half-ton “separation ring,” which connects satellites to the rest of the rocket, then detaches to propel it into space.
Fortunately, no one was harmed in either of these cases, but they raise unprecedented legal questions about who can be held liable for damage caused by space debris, and to what extent.
The chances of being physically harmed by falling space debris are very low — as of 2022, most studies suggest that the likelihood of space debris hitting any one individual, around the world, is 1 in 10,000. That’s because most of the Earth is ocean, and because most space debris tends to burn up in the atmosphere as it descends, long before it reaches the ground.
More broadly, as space debris enters the atmosphere, it releases metallic aerosol particles as it burns up, which a recent study warns may warm the Earth’s middle and upper atmosphere by up to 1.5 degrees Celsius, alter wind speeds, and harm the ozone layer. According to a 2024 report from the United Nations, the world would warm by 3.1 degrees Celsius unless we take substantial action to cut emissions now, and this threat may make our time gap even narrower.
Scientists don’t fully understand the impacts of space debris yet, but two questions have already emerged: How can we, legally and financially, protect people from this unpredictable threat? And how do we force world governments to take responsibility for space pollution, and take steps to clean it up?
Few Legal Guidelines Exist
Legally, these questions are not easily answered. The Outer Space Treaty, an international agreement on some basic rules governing conduct in space, states that space objects are owned by the launching state. However, people disagree on whether this extends to space debris, and it might be difficult to trace debris back to its country of origin. There is also concern that bad actors may make false, or indeterminate claims about where space debris came from to manufacture hostility towards other nations.
The Treaty also lays out no incentive to clean space debris, so no country has made any effort to do so. The U.S. and other nations program satellites to move in a certain trajectory that is designed to make them fall back to Earth within 25 years, towards Point Nemo in the Pacific Ocean, the most remote place on Earth. However, this is an imperfect solution, because it then just pollutes the ocean, and many scientists believe that we must do more.
So, even if space pollution sounds like something out of a movie, it still is — or should be — a real concern for environmentalists everywhere. In the same way that degradation of one ecosystem can impact the wider environment, pollution in space has immediate consequences for Earth.
While none of us can clean up space debris, we can clean up planet Earth – the GREAT GLOBAL CLEANUP gathers communities around the world to get rid of plastic pollution, regardless of its source, making our ecosystems cleaner and safer. Additionally, our CLIMATE EDUCATION COALITION works to empower people from every field to combat environmental problems, which can include the astronomers of tomorrow.
In space, no one hears about the threat of pollution. But together, we can work to raise awareness, and prevent an interstellar invasion of our own making.
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