GS Paper III

News Excerpt:

In the past decades, a new and unexpected hazard has emerged with increasing space activities: orbital or space debris.

Instances that led to Orbital debris:

• The debris problem in space has been exacerbated by various incidents, including the -
• 1996 French satellite damage,
• the 2009 Russian spacecraft collision with the U.S. Iridium spacecraft,
• China's 2007 anti-satellite test.
• In 2019, India completed an anti-satellite missile test, creating a cloud of at least 400 pieces of debris and increasing the risk of impacts to the International Space Station (ISS) by 44% over a 10-day period.

Mega Constellations – adding to the problem of orbital debris:

• Several companies are planning vast new groups of satellites, called mega constellations, that will beam the internet down to Earth.
• These companies, which include SpaceX, Amazon’s Project Kuiper, OneWeb Corporation and Canada’s Telesat, plan to launch thousands of satellites to achieve global satellite internet coverage.
• If successful, there could be thousands of additional satellites in orbit. This also means more collision avoidance manoeuvres will need to be done.

Spacecraft Maneuvering:

• NASA has guidelines to assess the threat of such manoeuvres, ensuring the International Space Station's and its crew's safety.
• In 2020, NASA fired the Progress resupply module's engines to boost altitude to avoid a rocket fragment collision.
• Since 1999, the ISS has conducted 29 debris avoidance maneuvers, including three in 2020.
• In 2019, the European Space Agency (ESA) performed its first satellite manoeuvre to avoid collision with a mega constellation.

Risks posed by Orbital debris:

• Space junk poses a significant risk to spacecraft operating in Low Earth Orbit (LEO) due to its fast-moving nature.
• Even small paint flecks can damage spacecraft, leading to the replacement of some space shuttle windows.
• Millimetre-sized orbital debris is the highest mission-ending risk for spacecraft operating in low Earth orbit.
• Debris in space travels approximately 10 kilometres per second, making collisions with large objects even more dangerous.
• The amount of debris in geostationary orbit is less than in low-Earth orbit (LEO), where debris is most dense and orbital velocities are highest.
• Debris in the LEO will re-enter the atmosphere quickly, while junk in higher orbits may remain in space indefinitely.

Initiatives to control orbital debris:

• Guidelines:
  • NASA issued guidelines in the mid-1990s to address the growing orbital debris hazard, followed by other international agencies.
  • In 2002, the Inter-Agency Space Debris Coordination Committee adopted a consensus set of guidelines for coordinating activities related to man-made and natural debris in space.
  • The United Nations requires companies to remove their satellites from orbit within 25 years after their mission ends, but this is challenging to enforce due to satellite failure.
  • Entities like the United Nations Committee on the Peaceful Uses of Outer Space (COPUOS) and the European Space Agency are collaborating to establish guidelines for space travel, satellite deorbit, and junk removal.
  • Other governmental efforts include the United States' Space Policy Directive-3 and the Orbital Debris Implementation Plan.

• Active De-orbiting measures:
  • Active deorbiting is crucial for collecting and moving debris to a lower orbit, enabling faster deorbitation.
  • Harpoon Systems: It involves deploying a device that can physically capture a piece of debris. This method is particularly useful for capturing larger pieces of debris.
  • Nets and Snares: These are designed to envelop or capture debris, especially smaller objects.
    • A spacecraft equipped with a net or snare can approach the debris, deploy the capturing mechanism, and secure the object for subsequent removal.
    • Surgery Satellite Technology's RemoveDEBRIS mission 2018 practised grabbing a satellite with a giant net.
  • Robotic Arms: It can grasp, manipulate, and secure debris. These arms can be attached to a dedicated debris removal spacecraft, providing a versatile means of interacting with different types and sizes of debris.
  • Electrodynamic Tethers: These use an electrically conductive tether to interact with the Earth’s magnetic field, generating thrust.
    • It changes the orbit of the debris, causing it to re-enter the Earth’s atmosphere and burn up.
    • Japan's space agency, JAXA, is testing an electrodynamic tether (EDT), an electronic space whip spanning nearly 2,300 feet long, to knock debris out of orbit and burn it in Earth's atmosphere.
  • Propellantless Deorbit Devices: These include solar sails or aerodynamic drag devices.
    • These technologies harness natural forces, like solar radiation pressure or atmospheric drag, to gradually lower the orbit of the debris until it re-enters the Earth’s atmosphere.
  • Ground-Based Lasers: These nudge the debris by imparting momentum through laser ablation.
    • This method requires precise targeting and coordination to avoid causing damage to operational satellites.
    • Tohoku University researchers are developing a contactless de-orbiting solution, where a satellite fires a particle beam at debris, causing it to slow, lower its orbit, and enter Earth's atmosphere.

India’s Initiatives on Space Debris:

• Project NETRA - It is an early warning system in space to detect debris and other hazards to Indian satellites.
• Centre for Space Debris Research – It has been set up by ISRO to monitor and mitigate the threat of space debris.
• System for Safe and Sustainable Operations Management (IS4OM) was set up by 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 also carried out 21 collision avoidance manoeuvres of Indian operational space assets in 2022 to avoid collisions with other space objects.

Way forward:

• Addressing space debris requires international cooperation, advanced technology, and sustainable operations.
• Collaboration between space-faring nations, space agencies, and international bodies like the United Nations Committee on the Peaceful Uses of Outer Space (COPUOS) is crucial for responsible debris removal.
• COPUOS develops guidelines and promotes international cooperation in space activities.
• The United Nations mandates activities in outer space to minimize their effects on the environment and Earth, aligning with the 2030 Agenda for Sustainable Development.
• The Indian philosophy of “Vasudhaiva Kutumbakam” should be transformed into “One Universe, One Family”, emphasising the universe's universality.