Pulsed Laser Interactions with Space Debris: Target Shape Effects

TL;DR

This paper investigates how the shape of space debris affects recoil dynamics during laser ablation for de-orbiting, developing analytical models to predict momentum transfer and spin changes, which are crucial for effective debris mitigation.

Contribution

It introduces a simple analytical technique to calculate shape-dependent recoil and spin effects during laser ablation of space debris, enhancing predictive capabilities for debris removal strategies.

Findings

Shape and orientation significantly influence recoil direction and magnitude.

Ablation can alter the spin state of debris targets.

Shape effects on momentum transfer are similar to, but distinct from, photon pressure effects.

Abstract

Among the approaches to the proposed mitigation and remediation of the space debris problem is the de-orbiting of objects in low Earth orbit through irradiation by ground-based high-intensity pulsed lasers. Laser ablation of a thin surface layer causes target recoil, resulting in the depletion of orbital angular momentum and accelerated atmospheric re-entry. However, both the magnitude and direction of the recoil are shape dependent, a feature of the laser-based remediation concept that has received little attention. Since the development of a predictive capability is desirable, we have investigated the dynamical response to ablation of objects comprising a variety of shapes. We derive and demonstrate a simple analytical technique for calculating the ablation-driven transfer of linear momentum, emphasizing cases for which the recoil is not exclusively parallel to the incident beam. For the purposes of comparison and contrast, we examine one case of momentum transfer in the low-intensity regime, where photon pressure is the dominant momentum transfer mechanism, showing that shape and orientation effects influence the target response in a similar, but not identical, manner. We address the related problem of target spin and, by way of a few simple examples, show how ablation can alter the spin state of a target, which often has a pronounced effect on the recoil dynamics.