Orbital Debris Removal: Astroscale's Mission to Clean Up Space

The space directly above Earth is becoming dangerously crowded. With thousands of defunct satellites and spent rocket stages orbiting our planet at thousands of miles per hour, the risk of catastrophic collisions increases every year. Astroscale, a private orbital debris removal company, is tackling this massive engineering challenge head-on. Their recent missions focus on inspecting and eventually removing these dangerous pieces of space junk to ensure orbit remains safe for future generations.

The ADRAS-J Mission: A World First

In February 2024, Astroscale launched a groundbreaking mission called ADRAS-J (Active Debris Removal by Astroscale-Japan). Launched aboard a Rocket Lab Electron rocket from New Zealand, this satellite was designed for a specific and incredibly difficult task: to track down and closely inspect a large piece of existing space debris.

The target is an 11-meter long upper stage of a Japanese H-2A rocket. This massive piece of metal, weighing approximately three tons, has been floating in Low Earth Orbit (LEO) since 2009. Unlike active satellites, this rocket body is “non-cooperative.” It does not emit GPS signals, it does not communicate with the ground, and it does not have visual markers or docking plates to help another vessel latch onto it.

The Inspection Phase

Astroscale successfully maneuvered the ADRAS-J satellite to within a few hundred meters of the rocket body. Using onboard cameras and LiDAR sensors, the spacecraft performed complex Rendezvous and Proximity Operations (RPO). This involves matching the speed and rotation of the debris perfectly.

In mid-2024, Astroscale released stunning images taken from just 50 meters away. The satellite successfully performed a “fly-around” maneuver, inspecting the condition of the rocket body to see how badly the harsh environment of space had degraded the structure over the last 15 years. This data is critical for the next step: grabbing it.

How Astroscale Plans to Remove the Junk

Astroscale creates different technologies for different types of debris. Their approach generally falls into two categories: End-of-Life (EOL) services for new satellites and Active Debris Removal (ADR) for old junk already up there.

Magnetic Capture (ELSA-d)

For new satellites launching today, Astroscale proposes installing a simple magnetic docking plate before they leave Earth. In 2021, they launched the ELSA-d mission to demonstrate this. The servicer satellite successfully released a client satellite and then used a magnetic capture mechanism to snatch it back out of orbit. This proves that if satellite operators prepare ahead of time, cleaning up dead satellites is relatively straightforward.

Robotic Arms for Legacy Junk

The H-2A rocket body targeted by the ADRAS-J mission does not have a magnetic plate. To remove objects like this, Astroscale is developing robotic arm technology.

Following the successful inspection by ADRAS-J, the Japan Aerospace Exploration Agency (JAXA) selected Astroscale for the next phase, known as ADRAS-J2. The goal of this future mission is to return to the same rocket body, match its tumble rate, grab it using a robotic arm, and then use thrusters to push it down into the Earth’s atmosphere. The friction from re-entry will burn up both the servicer and the debris safely over the ocean.

The Growing Threat of Kessler Syndrome

The urgency behind Astroscale’s technology is driven by a theory known as the Kessler Syndrome. Proposed by NASA scientist Donald Kessler in 1978, this scenario suggests that if the density of objects in Low Earth Orbit gets high enough, a single collision could create a cascade effect.

  1. Initial Collision: Two large satellites crash, creating thousands of pieces of shrapnel.
  2. Cloud Expansion: This debris spreads out into a ring around the Earth.
  3. Chain Reaction: The new debris hits other satellites, creating even more junk.

If this happens, certain orbits could become unusable for decades or centuries. We are already seeing the warning signs. In 2009, a defunct Russian satellite collided with an active Iridium communications satellite, creating over 2,000 pieces of trackable debris.

The European Space Agency (ESA) estimates there are currently more than 1 million objects larger than 1 centimeter in orbit. At speeds of 17,500 miles per hour, even a 1-centimeter bolt hits with the energy of a hand grenade.

The Business of Space Cleanup

Historically, no one wanted to pay for garbage collection in space. However, the economics are changing. Governments and private companies are realizing that their billion-dollar space assets are at risk.

  • JAXA (Japan): The Japanese space agency is a primary funder of Astroscale’s current ADRAS-J missions, treating debris removal as a national infrastructure priority.
  • UK Space Agency: Astroscale has a significant presence in the UK and has received funding to develop satellite servicing capabilities there.
  • ESA and ClearSpace: The European Space Agency is funding a competitor mission called ClearSpace-1, targeting a payload adapter from a 2013 Vega rocket launch. This mission is slated for 2026.

As companies like SpaceX launch thousands of Starlink satellites, regulators are becoming stricter. The US Federal Communications Commission (FCC) recently implemented a “5-year rule,” requiring operators to deorbit their satellites within five years of completing their mission. This regulatory pressure creates a massive market for companies like Astroscale to offer “tow truck” services for satellites that fail to deorbit themselves.

Frequently Asked Questions

Why can’t we just shoot the debris down? Shooting debris with missiles, as demonstrated by anti-satellite (ASAT) tests conducted by nations like Russia and China, is the worst possible solution. It shatters one large object into thousands of smaller, untrackable pieces, significantly increasing the risk to other spacecraft.

How does Astroscale make money? Currently, much of their revenue comes from government contracts (like JAXA) to demonstrate the technology. In the future, they plan to charge satellite operators a subscription or service fee to remove failed satellites, acting as an insurance policy for orbital sustainability.

Is the debris brought back to Earth? No. It is not brought back to the surface. The goal is to push the debris into the atmosphere. The intense heat generated by air friction at high speeds causes the debris to vaporize and burn up completely before it hits the ground.

What happens if the target is spinning? This is the hardest part of the job. Many dead satellites “tumble” chaotically. Astroscale’s software must analyze the spin visually and fire thrusters to synchronize the servicer satellite’s rotation with the debris. It is like trying to refuel a car while both cars are doing donuts in a parking lot.