Space debris

noun (uncountable)

/speɪs ˈdɛbriː/

Non-functional artificial objects — defunct satellites, discarded rocket stages, mission-related fragments, and collision debris — orbiting the Earth and posing collision risks to operational spacecraft. As of 2024, the European Space Agency (ESA) estimates over 36,500 objects larger than 10 cm, 1 million objects between 1–10 cm, and 130 million fragments between 1 mm–1 cm in Earth's orbit. In UPSC context, the Kessler Syndrome (a self-sustaining cascade of collisions), India's ISRO Space Situational Awareness Control Centre (ISSAC), India's anti-satellite (ASAT) test Mission Shakti (27 March 2019, resulting in ~400 trackable fragments), and the UN COPUOS (Committee on the Peaceful Uses of Outer Space) debris mitigation guidelines are key examination themes in GS3.

✍️ Usage in a UPSC answer

India's Mission Shakti ASAT test of March 2019 — while demonstrating a credible space-denial capability — generated an estimated 400 trackable debris fragments in low Earth orbit, underscoring the inherent tension between strategic deterrence through demonstrated space-warfare capabilities and the collective responsibility to preserve orbital commons for peaceful use.

Synonyms

orbital debrisspace junkorbital wastesatellite debrisspace fragments

Antonyms

operational satelliteactive spacecraftfunctional orbital asset

🌱 Word Family

space debris (n), orbital debris (n, synonym), debris cloud (n phrase), Kessler Syndrome (n phrase), space junk (informal n), active debris removal (n phrase, ADR)

🔡 Root

French débris = broken-down remains, rubble (from débriser = to break apart, dé- = intensive prefix + briser = to break); space from Latin spatium = extent, area

📜 Etymology

The French word débris ('rubble, fragments') entered English in the 18th century from French débriser ('to break apart'). It is pronounced in English retaining the French final syllable (/ˈdɛbriː/). Space in the extraterrestrial sense derives from Latin spatium. The compound space debris gained currency in the 1970s with the proliferation of satellite launches following Sputnik (1957).

🧠 Memory Hook

SPACE DEBRIS: débris is French for rubble — imagine a demolition site in orbit. The Kessler Syndrome (named after NASA scientist Donald Kessler, 1978) is the nightmare scenario: one collision triggers a chain, turning LEO into an impassable debris field. Mission Shakti 2019 + Kessler Syndrome = the complete UPSC answer on this topic.

📝 Seen in UPSC Question Papers

Prelims 2019 — Space Technology

Real UPSC previous-year questions whose text uses “Space debris” — proof this word earns its place on your list.

🔬 Science & Technology 📖 Seen in: Emerging Technologies — AI, Quantum Co...

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