ANALYSIS OF THE NONSTATIONARY DEBRIS CLOUD PINCH ZONE

This paper presents an analysis of the underlying causes and features of the debris cloud nonstationary pinch zone. This pinch zone is class ified as ''nonstationary'' because it drifts inertially as the debris cloud flies through it. The more familiar half- and whole-revolution p inch zones are classified as ''stationary'' because they do not move i nertially under Keplerian motion. It was found that the nonstationary pinch zone consists of a curved surface, or sheet, of positions inside the debris cloud in which debris density becomes very large, and in t he case of Keplerian motion approaches infinity. The analysis was base d on the use of Jacobians to determine regions of infinite density and to expose the complex relative motion that underlies the phenomenon. The understanding of pinch zones is important because, due to their ch aracteristic high fragment density, they pose the greatest collision h azard to orbiting assets.