What size threshold generally defines cataloged and tracked space debris objects?
Objects larger than 10 centimeters
The inventory of tracked space objects relies heavily on object size because smaller fragments are exceedingly difficult to monitor consistently across orbital paths. Agencies specifically catalog objects that are large enough to be reliably observed by ground and space-based sensors. The established lower boundary for inclusion in these major databases, such as those maintained by the European Space Agency's Space Debris Office, is typically set at objects exceeding 10 centimeters in diameter. This threshold effectively filters out the hundreds of thousands of smaller fragments between 1 cm and 10 cm, and the millions of even tinier paint flecks, even though these microscopic particles pose a significant kinetic energy threat due to their velocity.
