A graveyard orbit is an orbit 36,050 kilometres above the Earth's surface (higher than most common operational orbits) where decommissioned satellites are moved to reduce the possibility of them colliding with other functional satellites and generating space debris. In this article, we will discuss in detail regarding Graveyard Orbit which will be helpful for UPSC exam preparation.

Graveyard Orbit

Need for Graveyard Orbit

• There are currently over a thousand artificial satellites orbiting the planet at various altitudes (and inclinations) above the ground. These, however, are only the operational ones.
• If you include defunct satellites and every 'good-sized' piece of old satellite circling our planet, the figure rises dramatically.
• The problem with so much space junk is that it can (and often does) endanger satellites working or travelling through orbits.
• Modern rocket launches are carried out after days and days of research and analysis of numerous factors, one of which is the problem of space garbage, which has a direct impact on the safety and integrity of the launched rockets and their payload.
• In the primitive days of space exploration, scientists and space engineers didn’t think much about the distant future of the satellites they launched.
• In other words, they did not worry about what would happen to all the rockets and satellites they were putting into space once they became inoperative.
• These days, however, there is so much space garbage around our planet that even a small-scale collision between two objects can trigger a chain reaction that could potentially end in a catastrophe.

What is Space Debris?

• In its broadest sense, space debris refers to both natural micrometeoroid and artificial orbital debris components of the space environment.
• According to the European Space Agency, there are currently over 7,500 pieces of space junk in orbit that are at least 4 inches wide.
• This free-floating space debris poses a risk to operational satellites, and colliding with it can render the satellites inoperable.
• Donald Kessler, a scientist at the National Aeronautics and Space Administration (NASA), coined the term "Kessler Syndrome" to describe this condition in 1978.
• According to the report, if there is too much space junk in orbit, it could start a chain reaction in which more and more objects collide and create new space junk, eventually rendering Earth's orbit useless - a Domino Effect.

Ways to Dispose of Satellites

• We dispose of broken satellites using one of two methods.
  • First, we slow down the defunct satellite and let it fall back to Earth, where it will burn up in the atmosphere during re-entry.
  • Second, we launch the inoperative satellite into a higher orbit around the planet, where it will remain for hundreds of years while staying out of the way of operational satellites.

• As you may be aware, various satellites orbit our planet at various altitudes; some travel very close to it (a few hundred kilometres above the ground, such as the ISS), while others revolve tens of thousands of kilometres above Earth (such as geostationary satellites).
• The method of disposal of an inoperative satellite is heavily dependent on its distance from our planet.

1) Satellites that Orbit Close to Earth

• To discard a satellite that orbits close to Earth, space engineers change its orbit slightly so that it enters a lower orbit and burns up on its own over a 25-year period (after its mission is completed). This is referred to as the '25-year rule' for satellites.
• If the satellite in question is too large to be completely burned up during re-entry, the last bit of satellite fuel is used to deliberately slow it down and de-orbit it so that the debris falls over a remote area hundreds of miles away from any civilization.
• This remote area, located in the southern Pacific Ocean, is aptly nicknamed "Spacecraft Cemetery."

2) Satellites that Orbit Far from Earth

• Slowing down and de-orbiting a satellite that is very high above Earth would require a lot of fuel, which a satellite nearing the end of its operational life lacks.
• As a result, rather than slowing its orbital speed, the satellite is pushed into a higher orbit known as the "graveyard orbit."
• The advantage of putting dead satellites into junk orbit is that they stay up there and continue revolving around the planet for hundreds of years before losing altitude.

Conclusion

The Graveyard Orbit exists in the vast darkness of deep space, far beyond the reaches of normal orbits. It is filled with the "bodies" of dead satellites. Satellites, like everything else, have a finite lifespan. They have a limited fuel capacity and must endure the harsh conditions of launch, orbiting Earth at thousands of miles per hour, and the extremes of outer space.

FAQs

MCQs

1. What is the main purpose of the Graveyard Orbit?

A) To store space debris
B) To dispose of defunct satellites safely
C) To monitor space traffic
D) To place active satellites at higher altitudes

2. How high is the Graveyard Orbit positioned?

A) Above the low Earth orbit (LEO)
B) Above the geostationary orbit (GEO)
C) Below the low Earth orbit (LEO)
D) Below the geostationary orbit (GEO)

3. Why is space debris a growing concern?

A) Because it provides resources for new satellite development
B) Because it can interfere with the operation of active satellites
C) Because it enhances satellite signal reception
D) Because it helps control space traffic

4. What is the primary environmental concern with Graveyard Orbits?

A) Accumulation of debris in lower orbits
B) Potential for collisions with other space objects
C) Environmental damage to Earth’s atmosphere
D) Contamination of the Moon’s surface

5. What technology is used to move satellites to Graveyard Orbits?

A) Advanced propulsion systems
B) Gravitational slingshots
C) Solar-powered thrusters
D) Electrodynamic tethers

GS Mains Questions and Model Answers

Q1: Analyze the role of Graveyard Orbits in space sustainability and safety.

Answer: Graveyard Orbits play a critical role in maintaining the sustainability and safety of space activities. By moving defunct satellites to higher orbits, they reduce the risk of collisions with active satellites in operational orbits. This ensures the safety of valuable space assets and reduces the creation of space debris. While Graveyard Orbits offer a safe disposal solution, it is important to manage these regions effectively to prevent overcrowding and ensure that they do not become another source of space hazards. Proper space debris management is essential to the continued exploration and utilization of space.

Q2: Discuss the environmental implications of growing space debris and its management strategies.

Answer: The increasing accumulation of space debris poses significant environmental challenges, particularly in terms of collision risks with operational satellites, which can lead to more debris creation. Effective management strategies include active debris removal, use of satellite end-of-life protocols (such as moving to Graveyard Orbits), and designing satellites with built-in deorbiting mechanisms. Collaborative international efforts are also crucial in mitigating the impact of space debris. The goal is to maintain the long-term sustainability of space activities by ensuring that the debris does not become an insurmountable obstacle to space exploration.

Q3: How do international collaborations help in managing space debris and ensuring safe space exploration?

Answer: International collaboration is essential in managing space debris and ensuring safe space exploration. Global cooperation enables the sharing of space debris tracking technologies, joint development of debris removal techniques, and unified regulatory frameworks for satellite design and end-of-life disposal. Collaborative agreements such as the UN’s Space Debris Mitigation Guidelines foster collective responsibility among space-faring nations to reduce debris creation and promote sustainable practices. Working together, nations can address the shared challenge of space debris, safeguarding both the space environment and the future of space exploration.

Previous Year Questions on Graveyard Orbits and Space Sustainability

1. UPSC CSE Prelims 2017:

Question: The concept of Graveyard Orbit is related to which of the following space-related activities?

A) The placement of communication satellites
B) The safe disposal of defunct satellites
C) The construction of space stations
D) The movement of satellites to higher altitudes

Answer: (B)

Explanation: The Graveyard Orbit is specifically designed for the safe disposal of defunct satellites. It ensures that inactive satellites are moved to a region above the geostationary orbit, thus preventing them from interfering with active spacecraft.

2. UPSC CSE Mains 2021 (General Studies Paper 3):

Question: Evaluate the significance of international cooperation in space debris management.

Answer: Space debris management requires a collaborative effort across nations to ensure the safety and sustainability of space operations. International cooperation enables the sharing of technology for debris tracking and removal, as well as the establishment of global standards for satellite design and end-of-life procedures. Space-faring nations can also collaborate on research and innovations aimed at reducing debris creation and developing more efficient debris removal technologies. Such global cooperation is essential in preserving the space environment for future generations and maintaining the safety of operational satellites.