TABLE OF CONTENTS Although the natural meteoroid environment has been considered in the designs of past and existing spacecraft, future satellite designs will have to take account of space debris in addition to the natural environment.
Man-made space debris differs from natural meteoroids because it is in permanent Earth orbit during its lifetime and is not transient through the regions of interest. As a consequence, a given mass of material presents a greater problem in the design and operation of spacecraft because of the extended time period over which there is risk of collision.
Past design practices and deliberate and inadvertent explosions in space have created a significant debris population in operationally important orbits. The debris consists of spent spacecraft and rocket stages, separation devices, and products of explosion. Much of this debris is resident at altitudes of considerable operational interest. Products larger than 10 cm 2 in low orbits can be observed directly. The existence of a substantially larger population of small fragments can be inferred from terrestrial tests in which the particle distributions from explosions have been assayed. From these tests it is reasonable to infer small particle numbers, of the order of 10,000 for each low-intensity explosion and several million for high-intensity explosions.
Two types of space debris are of concern: 1) large objects whose population, while small in absolute terms, is large relative to the population of similar masses in the natural flux (by a factor of about 1000); and 2) a large number of smaller...
