1. What is Space Debris?

Space debris encompasses all defunct artificial objects in Earth orbit—spent rocket stages, inactive satellites, fragment clouds, and paint flakes. Over 35,000 tracked objects larger than 10 cm and over 100 million millimeter-sized fragments currently threaten space operations.

2. Hypervelocity Physics: Why 1 cm Fragments Act Like Grenades

Objects in low Earth orbit travel at 7 to 8 km/s (17,500 mph). Kinetic energy scales with the square of velocity ($E = \frac{1}{2}mv^2$), meaning even a 1 cm aluminum fragment carries explosive kinetic energy equivalent to a hand grenade upon impact.

3. The 2009 Iridium 33 & Cosmos 2251 Collision

On February 10, 2009, an active US Iridium 33 communication satellite collided with a defunct Russian military Cosmos 2251 satellite at 11.7 km/s relative speed, generating thousands of hazardous fragments that remain in orbit today.

4. Kessler Syndrome: The Cascade Threat

Proposed by NASA scientist Donald Kessler, this scenario describes a cascading runaway collision chain where colliding debris generates more fragments, rendering low Earth orbit permanently unusable for future generations.