What is Kessler Syndrome and why it could lead to a potential space disaster

Thousands of satellites and rockets have been sent to space ever since humans started exploring this vast and fascinating world of infinite mysteries. These satellites serve multiple purposes, helping scientists make space discoveries, observations and also provide access to entertainment, Wifi, GPS and television. However, not all satellites remain active, and many become part of an ever-growing accumulation of

space debris

. Aging satellites, fragmented rocket parts, and smaller debris are contributing to an increasingly crowded orbital environment, which could eventually trigger a catastrophic scenario known as the

Kessler Syndrome

. It could set off a series of object collisions to the point where Earth’s orbit became unusable. Let’s understand all about

space junk

, its risks, and the implications of the Kessler Syndrome.

What is Kessler Syndrome?

Proposed by NASA scientist Donald Kessler in the year 1978, it is a hypothetical scenario where the space debris in Earth’s orbit creates a cascading chain reaction of collisions, producing more fragments and amplifying the risks to satellites, spacecraft, and astronauts. The phenomenon describes a future where the accumulation of orbital debris becomes so dense that it could render Earth’s orbit unusable for generations. This could jeopardize technologies like GPS, satellite communications, and weather monitoring, as well as interrupt our

space exploration

efforts.
Though the scenario is theoretical, the risks are real and growing. Space has become increasingly crowded due to an increase in satellite launches, accidental collisions, and intentional destruction of space objects. Experts warn that even small pieces of debris, traveling at high speeds, can cause catastrophic damage.

While efforts to being made to track and manage space debris, many scientists believe the early stages of Kessler Syndrome have already begun, which makes the future of space exploration bleak and raises a question about our reliance on satellite-based technologies.

What is space junk?

Space junk can refer to parts of objects, dead satellites, debris left by humans in space. There are many active satellites in space but there are also dead satellites that have failed or been left in orbit at the end of their mission. It also comprises of relatively smaller things like bits of debris, or paint flecks that have fallen off a rocket. Since the first space flight in 1957, there have been more than 650 “break-ups, explosions, collisions, or anomalous events resulting in fragmentation,” according to the

European Space Agency

.
The recent years have witnessed many satellite launches, rocket explosions, and weapons tests that have added to the junk.
Since the 1950s, approximately 50,000 tons of material have been launched into orbit. As of September 2024, over 13,000 tons of space objects remain in orbit. Of the 19,590 satellites launched since 1957, 13,230 are still in orbit, with 10,200 currently operational, according to the European Space Agency, citing data from the US Space Surveillance Network.
Even a fleck of paint left in the space has the incredible power to smash through metal as per NASA. Any piece of junk left in space can be extremely dangerous and even catastrophic.

Dangers of space junk

At the moment space junk doesn’t pose any danger to space exploration, but its growing size means the satellites have to move out of the way of the incoming space junk to ensure they don’t get hit or damaged.
Across all satellites, hundreds of collision avoidance manoeuvres are performed every year, including by the International Space Station (ISS), where astronauts live.

How to clear the space junk

One can avoid Kessler syndrome and prevent risk of collision by clearing up the space junk a bit.
The United Nations recommends that all companies remove their satellites from orbit within 25 years of completing their missions. However, enforcing this guideline is challenging, especially since satellites can fail unexpectedly.
To address this issue, innovative solutions have emerged, including using harpoons, nets, magnets, or lasers to remove defunct satellites by dragging them into Earth’s atmosphere to burn up. These techniques, while promising, are primarily suited for large satellites and not for smaller debris like paint chips or metal fragments, which must naturally re-enter the atmosphere over time.
Cleanup technology

, such as the Drag Augmentation Deorbiting Subsystem (ADEO), developed by the European Space Agency and HPS GmbH, offers passive deorbiting methods by increasing atmospheric drag, as demonstrated by a successful prototype in December 2022. However, such technologies remain experimental and costly, raising questions about funding.
Beyond cleanup, regulation plays a critical role. The United Nations’ recent Pact for the Future emphasizes discussions on space debris and traffic, though enforcement mechanisms are lacking.

Space policy

experts argue for national laws to hold space stakeholders accountable, with the United States potentially taking a leadership role in establishing clear frameworks.