**Clearing the Clutter: Halving Space Junk Hazards by Removing 50 Key Orbital Objects**

October 4, 2024

China’s Space Ambitions Spark Concerns Over Orbital Debris

Beijing’s accelerating deployment of massive satellite networks is raising alarms among space environmentalists.A growing number of discarded rocket components are remaining in orbit, posing a potential hazard to operational spacecraft and future missions.

Rising Debris Levels

Over the past 21 months, china has launched 21 of the 26 identified hazardous rocket bodies adrift in space, each weighing over 4 metric tons (approximately 8,800 pounds). Additional debris originated from launches conducted by the United States, Russia, India, and Iran. This trend coincides with China’s ambitious plans for two large-scale constellations: Guowang and Thousand Sails.

These constellations are comprised of thousands of communications satellites in low-Earth orbit. Initial launches began last year, and while the satellites themselves are relatively small and equipped with maneuvering capabilities, the upper stages of the rockets that delivered them are frequently abandoned in orbit.

Violations of International Guidelines

Experts note that nine upper stages abandoned following the deployment of Guowang and Thousand Sails satellites are projected to remain in orbit for over 25 years. This directly contravenes internationally recognized guidelines intended to mitigate the creation of long-term space debris.

Completing both the Guowang and Thousand Sails constellations will require hundreds of additional rocket launches. This prospect has heightened concerns about the proliferation of space junk, perhaps leading to increased collision risks for active satellites and manned spacecraft.

Technical and Economic Considerations

Several factors contribute to this practice. Some older Chinese rocket designs lack the capacity for controlled de-orbit maneuvers after payload deployment. Even rockets equipped with restartable engines may not carry sufficient fuel for a de-orbit burn, as reserving fuel reduces the amount of satellite payload that can be launched.

Despite these limitations, China possesses the technical capability to avoid leaving rocket bodies in orbit. The Long march 5 rocket,for example,has demonstrated de-orbiting capabilities with its YZ-2 upper stage. However, this practice is not consistently applied across all launches.

Credit: Astroscale

A Growing Legacy of Space debris

Since 2000, China has accumulated more defunct rocket mass in long-lived orbits than all other nations combined. Recent years have shown an acceleration of this trend as constellation deployments increase.

Did You Know? The Kessler Syndrome,a theoretical scenario proposed by NASA scientist Donald Kessler in 1978,predicts that a certain density of space objects could create a self-sustaining cascade of collisions,rendering space activities increasingly dangerous.

Nation	Rocket Bodies Abandoned (Last 21 Months)
China	21
United States	2
Russia	1
India	1
Iran	1

The long-term consequences of unchecked debris accumulation remain a serious concern. International cooperation and adherence to best practices are essential for ensuring the sustainable use of space for future generations.

Pro tip: Organizations like the World Economic Forum are driving initiatives for space sustainability. Staying informed about these efforts can provide valuable insights into the evolving landscape of space debris mitigation.

Understanding Space Debris

Space debris encompasses everything from defunct satellites and rocket bodies to fragments from collisions and explosions in orbit. These objects travel at extremely high speeds, posing a notable threat to functional spacecraft.Even small pieces of debris can cause significant damage upon impact.

Mitigation strategies include designing spacecraft for end-of-life de-orbit, developing active debris removal technologies, and improving space situational awareness to track and avoid collisions.

Frequently Asked questions About Space Debris

• What is space debris? Space debris refers to nonfunctional artificial objects, including defunct satellites, rocket stages, and fragments, orbiting Earth.
• Why is space debris a concern? It poses a collision risk to operational satellites and manned spacecraft,potentially disrupting vital services.
• What is being done to address the problem of space debris? Efforts focus on debris mitigation, removal technologies, and improved tracking.
• What role do international guidelines play in managing space debris? They establish best practices for responsible space operations,such as de-orbiting satellites.
• Is China alone in creating space debris? While China is currently the largest contributor, other nations and entities also generate debris.

What steps do you think international space agencies should take to address the growing debris problem? Share your thoughts in the comments below. Is China doing enough to mitigate its contribution to orbital debris?

How does the high velocity of orbital debris contribute to the severity of the threat it poses to operational spacecraft?

The Growing Threat of Orbital Debris

The realm beyond Earth is becoming increasingly crowded, not with operational satellites, but with space debris – defunct spacecraft, discarded rocket stages, and fragments from collisions. This orbital junk, also known as space waste, poses a important and escalating threat to active satellites, the International Space Station (ISS), and future space missions.the sheer velocity of objects in orbit (thousands of miles per hour) means even tiny pieces of debris can cause catastrophic damage.A focused effort to remove key pieces of this debris is crucial. Recent advancements,like those celebrated in the 35th anniversary of the Hubble Space Telescope,highlight our continued reliance on space-based assets,making debris mitigation even more vital.

Identifying the 50 Most Hazardous Objects

Determining which 50 objects represent the greatest risk isn’t simple. Several factors are considered,including:

* Size: Larger objects (over 10cm) are tracked more easily and pose a greater impact risk.

* Mass: Heavier objects deliver more energy upon impact.

* Orbital Altitude & Inclination: Objects in heavily populated orbits (like Low Earth Orbit – LEO) and those crossing multiple orbital planes are prioritized.

* Collision Probability: Complex modeling predicts potential collision scenarios.

* Fragmentation Potential: objects containing residual fuel or pressurized systems are more likely to break apart, creating more debris.

Organizations like the U.S. Space Force, ESA (European Space Agency), and commercial companies are actively cataloging and assessing the risk posed by individual pieces of debris. The 50 identified objects are likely a mix of:

* Dead Satellites: Non-functional satellites that continue to orbit.

* Upper Rocket Stages: Discarded portions of launch vehicles.

* Large Fragments: Pieces resulting from previous collisions or explosions.

Removal Technologies: A Toolkit for Orbital Cleanup

Several technologies are being developed and tested to actively remove space debris. These fall into a few main categories:

1. Tethering & Drag Augmentation: Deploying a long conductive tether increases drag, causing the object to re-enter the atmosphere and burn up. This is a relatively low-cost approach, but slow.
2. Robotic Capture: Using robotic arms or nets to physically capture debris and either de-orbit it or relocate it to a disposal orbit. This is technically challenging but offers precise control.
3. Harpooning: Firing a harpoon into the debris object to secure it for de-orbiting. This method is effective for non-cooperative targets.
4. Laser Ablation: Using ground-based or space-based lasers to slightly alter the debris’s trajectory, eventually causing it to re-enter the atmosphere. This is still in the early stages of development.
5. Ion Beam Shepherd: Utilizing an ion beam to exert a force on the debris, gently nudging it into a lower orbit.

Case Study: RemoveDEBRIS Mission

The RemoveDEBRIS mission, led by the University of Surrey, demonstrated several debris removal technologies in orbit. Launched in 2018, it successfully tested:

* Net Capture: Captured a small satellite using a net.

* Harpoon Capture: Successfully harpooned a target panel.

* Drag Sail Deployment: Deployed a drag sail to accelerate the re-entry of a target object.

This mission provided valuable data and validated the feasibility of active debris removal technologies.

The Legal and Political Landscape of Space Debris Removal

Removing orbital waste isn’t just a technical challenge; it’s also a legal and political one. Key considerations include:

* Ownership: Determining who has the right to remove debris, especially if it belongs to another country.

* Liability: Establishing responsibility for any damage caused during the removal process.

* Weaponization Concerns: Ensuring that debris removal technologies aren’t used for offensive purposes.

* International Cooperation: A global framework is needed to regulate debris removal activities and ensure equitable access to space.

The Outer Space Treaty of 1967 provides a foundational legal framework, but it doesn’t specifically address active debris removal. Ongoing discussions at the United Nations committee on the Peaceful Uses of Outer Space (COPUOS) are attempting to develop clearer guidelines.

Benefits of a Cleaner Orbital Surroundings

Halving the hazard from space junk by removing 50 key objects would yield significant benefits:

* Reduced Risk to Satellites: Protecting critical infrastructure like communication, navigation, and Earth observation satellites.

* Enhanced space safety: Improving the safety of human spaceflight, including missions to the ISS and beyond.

* Lower Insurance costs: Reducing the financial burden on satellite operators.

* sustainable Space Access: Ensuring long-term access to space for future generations.

* Preservation of Space Assets: Protecting the valuable resources already in orbit.

Practical Steps & Future Outlook

addressing the space debris problem requires a multi-faceted approach:

* Prevention: Designing satellites and launch vehicles to minimize debris creation.Implementing “passivation” procedures to vent residual fuel and discharge batteries at the