Orbital Debris
Orbital Debris, also known as space debris or space junk, refers to defunct human-made objects in space—principally in Earth orbit—which no longer serve any useful function. These objects include:
- Spent rocket stages
- Old satellites
- Fragments from disintegration, erosion, or collisions
History and Context
The issue of Orbital Debris has been recognized since the early days of space exploration:
- 1957: The launch of Sputnik marked the beginning of space debris when its rocket booster remained in orbit after the satellite was deployed.
- 1978: Donald J. Kessler published the 'Kessler Syndrome' theory, which theorizes that the density of objects in low Earth orbit (LEO) could reach a point where collisions could cause a cascade effect, making space activities and satellite operations in certain orbits extremely hazardous.
Over the decades, the accumulation of debris has increased significantly:
- By the early 2000s, it was estimated that there were over 13,000 pieces of debris larger than 10 cm in size tracked by the United States Space Surveillance Network.
- In 2007, China's anti-satellite missile test significantly increased the amount of debris in orbit by destroying the Fengyun-1C satellite.
- In 2009, an accidental collision between the Iridium-33 and the defunct Kosmos-2251 satellite further highlighted the problem.
Current Status
As of recent estimates:
- There are over 23,000 pieces of debris larger than 10 cm in size currently in Earth's orbit.
- Millions of smaller fragments, down to 1 mm in size, also exist but are not tracked due to their size.
- The velocity of these objects in LEO can reach speeds up to 28,000 km/h, making even small pieces extremely dangerous upon collision.
Mitigation Efforts
Efforts to mitigate Orbital Debris include:
- Design for Demise: Crafting satellites to burn up completely upon re-entry into Earth's atmosphere.
- Post-Mission Disposal: Ensuring satellites are deorbited or moved to a graveyard orbit at the end of their life.
- Active Debris Removal: Proposals and missions like RemoveDEBRIS aim to actively remove debris from space.
- Space Traffic Management: Regulations and guidelines to prevent collisions and manage space operations.
International Response
International cooperation has been key in addressing this issue:
External Links
Related Topics