Earth’s orbit is becoming increasingly crowded – not just with satellites and spacecraft, but with millions of fragments left behind from past missions.
This orbital debris ranges from defunct satellites to tiny metal shards, each capable of damaging active spacecraft travelling at blistering speeds. Even fragments smaller than a grain of sand can puncture equipment or compromise sensitive systems.
As space exploration accelerates, the challenge of monitoring and mitigating orbital debris has never been more urgent. Scientists warn that without solutions, cascading collisions could one day make parts of low-Earth orbit too hazardous to use.
SwRI’s new approach to space debris
In response to these risks, the Southwest Research Institute (SwRI) has created a micrometeoroid and orbital debris (MMOD) detection and characterisation system designed specifically for spacecraft protection.
Instead of focusing on deflecting space junk, the technology works like a forensic tool in orbit, capturing data every time debris strikes a spacecraft.
The system is built into spacecraft panels and equipped with sensitive detectors. When an impact occurs, the sensors record key details such as the particle’s velocity, size, and material composition.
The information is then transmitted back to Earth, where engineers can assess the risk and adapt future spacecraft designs.
Testing space collisions on Earth
To ensure the system works under realistic conditions, SwRI researchers recreated the violence of space impacts in their laboratory.
Using a high-powered light gas gun, they launched tiny projectiles at MMOD-equipped panels, replicating the speeds and conditions that spacecraft encounter in orbit.
The results demonstrated that the technology could detect not only when and where an impact happens but also the nature of the debris involved.
This capability gives mission operators new insight into threats that are normally invisible, since most collisions go unnoticed until damage becomes catastrophic.
Why this matters for future missions
One of the most promising aspects of the SwRI system is its potential to contribute to an orbital early warning network.
If a satellite detects a strike, it could alert other spacecraft in the same region to manoeuvre or prepare for potential impacts.
Over time, the system could help build a detailed orbital debris map, offering a clearer picture of the constantly shifting hazards above Earth.
For space agencies and private operators alike, this knowledge could be invaluable. With thousands of new satellites launching over the next decade, designing spacecraft that can withstand or avoid space junk will be key to maintaining safe operations.
Escalating dangers of space junk
The risk posed by orbital debris is growing every year. Anti-satellite weapons tests, accidental explosions, and ageing hardware are all adding to the debris cloud.
Left unchecked, the problem feeds itself: one collision can generate thousands of new fragments, increasing the likelihood of further impacts in a chain reaction known as the Kessler Syndrome.
By providing real-time data and long-term insights, SwRI’s detection system offers a proactive way to address this escalating threat.
While it cannot stop orbital debris from forming, it can help spacecraft survive in an increasingly dangerous environment.
A safer orbital environment
SwRI is now moving toward a flight-ready version of its MMOD detection system, with the ultimate goal of deploying it in orbit.
The hope is that one day, spacecraft won’t just endure collisions – they’ll learn from them, helping humanity chart a safer path through space.
As orbital debris continues to accumulate, innovations like this may be the deciding factor in whether low-Earth orbit remains usable for science, communication, and exploration in the decades to come.