Lasers and Nets: The Tech Cleaning Up Space Debris

Space is getting crowded. Decades of satellite launches and orbital missions have left a massive trail of garbage floating high above our heads. If you are interested in the future of space exploration, you have likely heard about the growing threat of orbital junk. Fortunately, aerospace engineers are developing incredibly creative solutions to clean up the mess.

The Growing Problem in Low Earth Orbit

Right now, Low Earth Orbit is a high-speed junkyard. The European Space Agency currently tracks over 36,500 pieces of space debris larger than 10 centimeters. They also estimate there are over 130 million fragments between 1 millimeter and 1 centimeter.

While a tiny screw might not sound dangerous on Earth, physics changes the rules in space. Objects in Low Earth Orbit travel at roughly 17,500 miles per hour. At those speeds, a paint fleck can crack a space shuttle window. A bolt can completely destroy a multi-million dollar communications satellite.

If we do not clean up this debris, we risk triggering the Kessler Syndrome. This is a theoretical scenario where one collision creates a cloud of shrapnel, which then hits other satellites, causing a chain reaction. Eventually, certain orbits could become completely unusable for generations. To prevent this, scientists are turning to very specific, highly advanced cleanup methods.

Catching Junk with Space Nets and Harpoons

One of the most promising early tests for debris removal came from the RemoveDEBRIS mission in 2018. Led by the Surrey Space Centre in the United Kingdom and backed by aerospace giant Airbus, this satellite was launched from the International Space Station to test multiple capture methods.

The most famous test involved a giant net. The RemoveDEBRIS satellite ejected a small target object, waited for it to float several meters away, and then fired a weighted net. The net successfully entangled the target. In a real-world scenario, the net would remain tethered to the main satellite. The main satellite would then drag the captured junk down into Earth’s atmosphere, where both would safely burn up upon reentry.

The same mission also successfully tested a miniature harpoon. The satellite fired a pen-sized titanium harpoon at 20 meters per second into a target panel, proving that high-speed projectiles can pierce and secure flat metal debris like dead solar panels.

Other organizations are following suit with physical capture methods. The European Space Agency has commissioned a mission called ClearSpace-1, which is scheduled to launch in 2026. Instead of a net, ClearSpace-1 will use four robotic arms to essentially hug a dead 250-pound payload adapter and drag it down into the atmosphere.

Zapping Debris with Lasers

Physical capture is effective but risky. If a net misses or a robotic arm accidentally bumps a spinning dead satellite, it could shatter the object and create thousands of new pieces of debris. This is where laser technology enters the picture.

Engineers are currently testing both ground-based and space-based laser systems to remove orbital junk. However, these lasers are not designed to blow up the debris like a science fiction movie. Blowing up a satellite just creates more dangerous shrapnel. Instead, the lasers use a process called laser ablation.

Here is how it works:

• A high-powered laser fires a continuous beam at a specific piece of space junk.
• The intense heat instantly vaporizes a tiny layer of the object’s surface.
• This vaporization creates a small burst of gas or plasma.
• That tiny burst acts like a miniature rocket thruster, pushing the debris in the opposite direction.
• By carefully angling the laser, engineers can slow the object down, causing its orbit to decay until it burns up in Earth’s atmosphere.

Several companies are racing to make this a reality. A Japanese startup named EX-Fusion is currently developing a ground-based laser system in Osaka. They plan to track space debris and fire lasers from the ground to gently nudge the junk out of orbit. Another Japanese company, Sky Perfect JSAT, is taking the opposite approach. They are designing a satellite equipped with an onboard laser designed to closely trail debris and shoot it into the atmosphere. Sky Perfect JSAT aims to have their laser satellite operational by 2026.

Magnetic Capture and Sticky Solutions

Beyond lasers and nets, companies are testing magnetic capture methods. Astroscale, a private aerospace company, launched its ELSA-d mission in 2021. This mission successfully demonstrated how a servicer satellite could use a powerful magnetic plate to dock with a tumbling piece of debris.

Astroscale is now working with the Japanese space agency (JAXA) on the ADRAS-J mission, which launched in early 2024 to carefully inspect a discarded rocket upper stage. The data gathered from this inspection will help engineers design the exact magnetic or robotic tools needed to capture it in the future.

Regulators are also stepping in to ensure new debris does not complicate these cleanup efforts. In 2022, the Federal Communications Commission enacted a strict “5-year rule.” This rule requires operators of low-orbiting satellites to safely dispose of their hardware within five years of completing their missions.

Frequently Asked Questions

What is space debris?

Space debris, or space junk, includes any human-made objects left in orbit that no longer serve a useful purpose. This includes dead satellites, spent rocket stages, paint flecks, and fragments from previous collisions.

Why do we need lasers instead of nets for some debris?

Nets require a cleanup satellite to get extremely close to the target, which requires a lot of rocket fuel and precise maneuvering. Lasers can nudge debris from a safe distance without physically touching it, removing the risk of accidentally smashing the target into more pieces.

Will space lasers accidentally hit working satellites?

No. The lasers designed for debris removal (like those being developed by EX-Fusion and Sky Perfect JSAT) require highly precise tracking systems. They are calibrated specifically for targeted pieces of tracked junk and do not have enough power to instantly destroy a passing satellite.

Do these cleanup methods bring the junk back to Earth?

Very rarely. Most debris is not brought to the ground. Instead, the nets, robotic arms, or lasers are used to slow the object down so it falls into Earth’s atmosphere. The intense heat of atmospheric reentry incinerates the debris completely.