Space junk can impact other objects at over 22,300 mph, faster than a speeding bullet. Collisions with those tiny pieces often leave pits and dings in the many satellites, telescopes, and other objects orbiting our planet.

Space debris represents a risk to spacecraft. Space debris is typically a negative externality. It creates an external cost on others from the initial action to launch or use a spacecraft in near-Earth orbit, a cost that is typically not taken into account nor fully accounted for by the launcher or payload owner.

Since these pieces of debris — of which there are approximately 1 million pieces 1 cm and larger — travel several times faster than a bullet, a collision between the debris or with active satellites could be devastating, destroying entire missions or creating large new debris fields. Today, close calls happen all too often.

Debris can travel at 18,000 mph, according to NASA. That's 10 times faster than the speed of a bullet, so even a tiny paint chip can rupture a spacesuit or damage delicate solar arrays and electronics on a satellite. Future and current missions can be at risk of debris strikes.