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Home Academy Debris & Re-entry Notable debris events (history)
LESSON 05 OF 6

Notable debris events (history)

Beginner ~6 min Slide deck Free

Today's orbital debris population isn't random — it's dominated by a handful of specific events. Understanding these events explains why certain altitude bands are congested and why space sustainability policy exists.

Today's orbital debris population isn't random — it's dominated by a handful of specific events. Understanding these events explains why certain altitude bands are congested and why space sustainability policy exists.

What this lesson covers

2007: Chinese ASAT test (Fengyun-1C)

In January 2007, China deliberately destroyed its own defunct weather satellite using a kinetic kill vehicle at 865 km altitude — the worst single debris-generating event in history.

2009: Iridium 33 / Cosmos 2251

The first accidental hypervelocity collision between two intact satellites. A defunct Russian Cosmos 2251 struck an active Iridium 33 comms satellite at ~790 km altitude.

Other defining events

Several other events have contributed significantly to the debris environment.

Events by impact

These three events alone account for a significant fraction of the total tracked debris catalogue. Upper-stage explosions add thousands more.

Key facts

💡This one event increased the total tracked debris population by roughly 25%.
A handful of events created most of today's debris. Altitude determines how long their legacy lasts.

The debris environment isn't a gradual accumulation — it's dominated by specific, identifiable events. Understanding them explains the current risk landscape and why debris mitigation guidelines focus so heavily on end-of-life disposal altitude.

All lessons in Debris & Re-entry
01What counts as debris~7 min02Conjunctions (close approaches)~7 min03Re-entry prediction (why it shifts)~7 min04Kessler Syndrome (the cascade risk)~6 min05Notable debris events (history)~6 min06Debris mitigation (guidelines & tech)~7 min
← Kessler Syndrome (the cascade risk)All 6 LessonsDebris mitigation (guidelines & tech) →
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