The risk of space debris falling to Earth and causing deaths and is growing, experts say

Today's scenery in space is not a pretty picture.

With the rate at which orbital launches are now occurring, some Earth orbits are so crowded and carry so many potentially dangerous, high-velocity pieces of defunct satellite litter and spent rocket stages that they could jeopardize humanity's future in space. That's the output from experts at the European Space Agency (ESA), waving a number of cautionary flags in its new Space Environment Report 2026. In brief, this disquieting appraisal from ESA points out that the number and scale of commercial satellite constellations continues to increase each year.

The report estimates that the casualty risk from reentering rocket upper stages alone was over four percent in 2024, having doubled since 2020, points out space environment specialist, Ewan Wright from the University of British Columbia, Vancouver, British Columbia, Canada. About 124 rocket stages reentered the atmosphere uncontrolled in 2024; over two per week, Wright told Space.com. "If that level is sustained for the next decade, the risk of someone somewhere being killed by rocket debris alone is 33 percent," he said.

Wright said that the casualty risk from satellites is also increasing, up to one percent in 2024. "The chance of an aircraft being struck, or airspace being closed due to a reentry, is also increasing as more objects reenter the atmosphere."

In Wright's view, these are avoidable risks. "All rockets should be required to do controlled reentries into the ocean, away from people and aircraft, to mitigate the risk entirely," he said.

Heavily congested

Earth's orbital environment is a finite resource. Too many satellites remain in heavily congested orbits at the end of their lives, creating a growing collision risk. Additionally, more than three intact satellites or rocket bodies are reentering Earth's atmosphere every day on average. At the same time, ten new payloads are launched daily.

One facet of using space that is quickly gaining in relevance is the concern about atmospheric pollution generated by reentries of space hardware. An ESA statement linked to the report suggests that a first task is to collect data on the extent and details of such pollution "to ensure a sound scientific basis for any mitigation measures, if needed."

Significant changes

Since the first issue of this report in 2016, there have been significant changes when it comes to humanity's usage of the space environment.

For the better, there has been a significant increase in the ability of space surveillance networks to reliably catalogue objects both in near geostationary orbits, as well as tagging launch traffic into low Earth orbit.

However, an increasing trend is the number of objects in orbit with an "unidentified" classification. That development reflects a growing gap between detected and catalogued "known origin" fragments.

This situation highlights the increasing complexity of the space environment, the report stresses, and the need for improved monitoring and space traffic management capabilities to be able to avoid collisions and fragmentations.

Health index

The ESA Environment Report 2026 is rife with key takeaways. And among them is a new trend they've added. That trend's bottom line: the casualty risk on the ground from fragments that survive atmospheric reentry is growing.

"Even though the numbers are low compared to everyday risks in life, the chance of a casualty increased in recent years due to increased traffic," the report notes.

This realization of what goes up can rain down is an outcome of more launches, more satellites in Earth orbit and more reentries into Earth's atmosphere of rocket stages and other space hardware.

An "ESA Space Environment Health Index" indicates that, in 2025, the long-term effect of current activities in space over time got an order of magnitude worse in just one year.

High price to pay

Active debris removal, the ESA report observes, is required to stop the growth of the number of objects over time that is caused by space debris causing new debris on their own through speedy smash ups, known as the Kessler syndrome.

"Some indicators show that the interest in and adherence to space debris mitigation measures is on the rise," the report points out, "but we need to be faster, more consistent and reliable. Without it, we are saddling future generations with a high price to pay for any activities in space."

To that point, even if no new satellites were launched, the debris population would continue to increase "because fragmentation events generate debris faster than they can naturally reenter the atmosphere." That means, the report adds, over time, this could make some orbital regions increasingly unsafe and potentially unusable.

Underscored in the report is that the greatest long-term threat is not simply the addition of new objects through launching more, but the self-sustaining cycle of collisions creating fragments that trigger further collisions.

'What would be desirable'

Is it fair to say this most recent appraisal by ESA best captures the situation compared to earlier studies?

In response, Stijn Lemmens, ESA's new Head of the Space Debris Office, told Space.com "yes it is." The report Lemmens said, "aims to aggregate all available and observable data in systematic and neutral fashion, providing year-on-year updates on trends."

This means modifications can occur between reports and elements, such as the future environment, Lemmens added, "are based on extrapolating how we behave now instead of what would be desirable."

Circular economy

ESA's long-term ambition, as reviewed in the report, is creating a circular economy in space through in-orbit servicing.

To do so means refueling, maintaining and repairing spacecraft in space, as well as recycling and reusing resources when manufacturing directly in space.

The paradigm change from "disposable" satellite to reuse and in-orbit servicing equates to a "seismic shift" throughout the space sector, the new report concludes.