Space Debris

Table of Contents

Context: The Australian Space Agency has confirmed that a large object found off the coast of western Australia is debris from an Indian Space Research Organisation (ISRO) rocket.

What is Space Debris?

Space debris, also known as space junk, refers to man-made objects that are no longer operational and orbit Earth.
These objects include defunct satellites, spent rocket stages, fragments from spacecraft collisions, and other discarded hardware from past space missions.
Space debris is a consequence of decades of human space exploration. As more satellites and rockets have been launched into space, and some of them have reached the end of their operational life, they become space debris.

Current State of Space Debris

According to the NASA, there are approximately 23,000 pieces of debris larger than a softball orbiting the Earth.
- They travel at speeds up to 17,500 mph, fast enough for a relatively small piece of orbital debris to damage a satellite or a spacecraft.
There are half a million pieces of debris the size of a marble or larger (up to 0.4 inches, or 1 centimeter), and approximately 100 million pieces of debris about .04 inches (or one millimeter) and larger.
There is even smaller micrometer-sized (0.000039 of an inch in diameter) debris.
The number of satellites orbiting Earth is expected to reach 60,000 by 2030, up from the current 9,000, and the amount of untracked debris is a cause for concern.

Impacts of Space Debris

Threat to Operational Satellites: Space debris can collide with operational satellites and spacecraft, causing damage or destruction. This can lead to the loss of critical communication, navigation, weather monitoring, and remote sensing services that rely on satellites.
Chain Reaction (Kessler Syndrome): A major collision between large objects could trigger a chain reaction known as the Kessler Syndrome, where the resulting debris creates more collisions, leading to a self-sustaining cascade that significantly increases the amount of debris in orbit.
Risk to Human Spaceflight: Space debris poses a risk to crewed spacecraft and astronauts on the International Space Station (ISS) and other future crewed missions. Even small debris fragments can cause severe damage to spacecraft hulls and vital systems.
Reduction of Orbital Slots: The accumulation of space debris in specific orbital regions can limit the availability of desirable orbital slots for future missions.
Impact on Earth from Re-Entry: When larger objects or satellites re-enter the Earth’s atmosphere, some parts may survive the heat of re-entry and reach the surface. While most of the Earth’s surface is water, there is still a risk of debris hitting populated areas.
International Tensions: As more countries engage in space activities, disputes may arise concerning responsibility for space debris mitigation and liability for damages caused by collisions involving spacecraft from different nations.

India

Project NETRA: It is an early warning system in space to detect debris and other hazards to Indian satellites.

Once operational, it will give India its own capability in Space Situational Awareness (SSA) like the other space powers.
Under NETRA, the ISRO plans to put up many observational facilities: connected radars, telescopes, data processing units and a control centre.
NETRA can spot, track and catalogue objects as small as 10 cm, up to a range of 3,400 km and equal to a space orbit of around 2,000 km.

System for Safe and Sustainable Operations Management (IS 4 OM): Setup by the ISRO in 2022, to continually monitor objects posing collision threats, predict the evolution of space debris, and mitigate the risk posed by space debris.
ISRO has also set up a Centre for Space Debris Research to monitor and mitigate the threat of space debris.

Global

The Liability Convention: The Convention on International Liability for Damage Caused by Space Objects, commonly known as the “Liability Convention,” is an international treaty that was adopted in 1972, by the United Nations General Assembly.

The convention addresses the issue of liability for damages caused by space objects to other states or their space objects on Earth and in outer space.
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 Inter-Agency Space Debris Coordination Committee (IADC): It is an international governmental forum, was established in 1993 to coordinate efforts between spacefaring nations to address the issue of space debris.
Clean Space initiative: The European Space Agency (ESA) has launched the Clean Space initiative, aimed at reducing the amount of space debris and promoting sustainable space activities.

Way Forward

Debris Mitigation Guidelines: Develop and implement debris mitigation guidelines and standards for spacecraft and rockets.
- These guidelines should include measures to minimize the creation of new debris, such as designing satellites with propulsion systems to deorbit them at the end of their operational life.
Active Debris Removal: Research and develop technologies for actively removing space debris from orbit.
- This can involve using robotic spacecraft to capture and deorbit defunct satellites or debris objects.
Space Situational Awareness (SSA): Enhance SSA capabilities to track and catalog space debris more effectively. This information is vital for space traffic management and collision avoidance efforts.
- SSA refers to the capability to monitor, track, and understand the space environment, including the location and behavior of space objects such as satellites, spacecraft, and space debris.
Gravitational Disposal: By using the gravity of the Moon or Earth to guide debris to crash into a designated uninhabited region or safely burn up in the atmosphere, the risk of future collisions can be reduced.
Satellite End-of-Life Disposal: Require satellite operators to plan for and execute end-of-life disposal maneuvers to remove satellites from operational orbits and move them to graveyard orbits or safely deorbit them.
International Cooperation: Establish agreements and guidelines that promote responsible behavior in space and address issues related to liability for space debris.
Reusable Launch Vehicles: Switching from single-use rockets to reusable launch vehicles will help cut down on the number of new debris produced during launches.