Space debris
Also called: Orbital debris, Space junk · Topic: Geographical Issues: Pollution, Urban Waste, Slums and Land Degradation · NCERT: Beyond NCERT
Meaning
Space debris (also called orbital debris or space junk) is any human-made object left in orbit that no longer does any useful work. It includes dead satellites, used rocket stages and the small pieces left when they break apart. These objects circle the Earth at very high speed, so even a small piece can badly damage a working satellite if the two collide. Each crash or break-up creates more pieces, so the problem can grow on its own. This matters because orbit, especially low Earth orbit (LEO), the band of space closest to the Earth, is a shared resource that every country's satellites depend on.
Example
In 2001, the upper stage of India's PSLV-C3 rocket broke apart in orbit and produced 371 pieces. Some fell back and burned up in the atmosphere, but 33 pieces were still in orbit at the end of 2025. Natural fall-back works, but it is very slow.
Don't confuse with
- Meteoroids: natural rocky or metal bits from comets and asteroids. Space debris is always human-made.
- Debris mitigation vs Active Debris Removal (ADR): mitigation means designing missions so they leave no new debris. For example, ISRO's Debris-Free Space Missions (DFSM) aims for this on all Indian missions by 2030. ADR means catching debris that is already in orbit and removing it.