Space Junk

Syllabus: GS3/Space

Context

  • As the number of satellites goes up, there is an increased concern about the Space Junk.

About

  • More than 10,000 active satellites are in orbit around the planet. This number is estimated to shoot up to more than 100,000 by the 2030s.
  • As the number of satellites goes up, so will the space junk pollution.

Space Debris

  • Junk from space objects falling to the earth involve relatively small fragments from rockets that survive the friction of the atmosphere.
  • Space junk can vary in size, from tiny bits like paint chips, to larger pieces like old satellites or rocket stages.
  • In recent times, a large chunk of a 25-tonne Chinese rocket fell into the Indian Ocean in 2021.

Space junk is caused by the following factors:

  • Defunct Satellites: Satellites that no longer function are left in orbit, contributing to debris.
  • Rocket Stages: Spent rocket stages and other launch vehicle parts that are abandoned after use remain in orbit.
  • Collisions: Objects in orbit often collide at high speeds, creating smaller debris fragments that increase the overall junk in space.
  • Spacecraft and Mission Debris: Parts of spacecraft or equipment released during missions (e.g., screws, paint flecks) contribute to the debris field.

Concerns

  • Collision Risks: High-speed debris collisions can create more fragments, leading to a self-perpetuating cycle that threatens satellites, spacecraft, and the space environment.
  • Threats to Operational Satellites: Debris can damage or destroy active satellites, increasing the risk to communication, weather, and navigation systems.
  • Atmospheric Pollution: Larger debris re-entering Earth’s atmosphere can burn up or fall into oceans, potentially releasing toxic materials.
  • Space Accessibility: The growing debris field limits the safe use of Earth’s orbital space, making future missions more difficult and costly.
  • Long-term Sustainability: The accumulation of debris could hinder space exploration for future generations, making space less accessible.

Convention on International Liability for Damage Caused by Space Objects

  • This convention is one of the several international agreements that complement the Outer Space Treaty, the overarching framework guiding the behaviour of countries in space. 
  • The Liability Convention came into force in 1972 and deals mainly with damage caused by space objects to other space assets, but it also applies to damage caused by falling objects on earth.
  • The Convention makes the launching country “absolutely liable” to pay compensation for any damage caused by its space object on the earth or to a flight in air.
    • The country where the junk falls can stake a claim for compensation if it has been damaged by the falling object.
    • The amount of compensation is to be decided “in accordance with international law and the principles of justice and equity”.
  • This provision of the Convention has resulted in compensation payment only once so far — when Canada sought damages from the then Soviet Union, for a satellite with radioactive substance that fell into an uninhabited region in its northern territory in 1978. 

Suggestions

  • Active Debris Removal (ADR): Develop and deploy robotic systems or spacecraft designed to capture and remove large debris from orbit, such as the ClearSpace-1 mission by the European Space Agency.
  • Improved Satellite Design: Use lightweight materials and create satellites that minimize debris generation during collisions or failures.
  • Increased Tracking and Monitoring: Enhance space situational awareness with better tracking systems to monitor debris and avoid collisions.
  • Collision Avoidance: Implement collision-avoidance maneuvers for operational satellites and space stations to prevent debris generation from accidental impacts.

Source: IE