The University of Southampton
University of Southampton Institutional Repository

Space debris cloud evolution in Low Earth Orbit

Space debris cloud evolution in Low Earth Orbit
Space debris cloud evolution in Low Earth Orbit
The Earth is surrounded by inoperative objects generated from past and current space missions. Because of the high orbital speed, even the impact with small fragments is a hazard to operational spacecraft as it could lead to the partial or complete loss of the mission. Therefore, it is important to assess the collision risk due to space debris considering small fragments, which are usually not included in space debris modelling because their large number would make simulations extremely complex. In this work, an analytical approach is developed to describe the evolution of debris clouds created by fragmentations in Low Earth Orbit. In contrast to traditional approaches, which follow the trajectory of individual fragments, with the proposed method the cloud behaviour is studied globally, so that the presence of small fragments can be modelled. This give a deeper insight into the dynamics of debris clouds and reduces the computational effort needed to estimate the consequences of a collision. A standard breakup model is used to describe the dispersion of the fragments in terms of characteristic length, area-to mass ratio and velocity. From the velocity distribution, the fragment spatial dispersion is derived. The cloud density is expressed by a continuous function that depends on the altitude and that is set as initial condition for the orbit propagation. Based on an analytical approach proposed in the literature for interplanetary dust and spacecraft swarms, the fragment cloud evolution in time is derived through the continuity equation, which is used to describe the variation of debris density considering the effect of atmospheric drag. The approach has been extended to express the cloud density as a function of multiple orbital parameters and to model additional perturbations such as the Earth’s oblateness. The method has been validated through the comparison with the traditional numerical propagation and then applied to study many breakup scenarios. The proposed approach proves to be flexible and able to study the collision risk coming from several breakup events and to evaluate the vulnerability of different targets. It is also applied to derive an index of the environmental criticality of spacecraft.
Letizia, Francesca
5f9f7e3f-0bf0-4731-9660-2d025def8392
Letizia, Francesca
5f9f7e3f-0bf0-4731-9660-2d025def8392
Colombo, Camilla
595ced96-9494-40f2-9763-ad4a0f96bc86

Letizia, Francesca (2016) Space debris cloud evolution in Low Earth Orbit. University of Southampton, Engineering and the Environment, Doctoral Thesis, 289pp.

Record type: Thesis (Doctoral)

Abstract

The Earth is surrounded by inoperative objects generated from past and current space missions. Because of the high orbital speed, even the impact with small fragments is a hazard to operational spacecraft as it could lead to the partial or complete loss of the mission. Therefore, it is important to assess the collision risk due to space debris considering small fragments, which are usually not included in space debris modelling because their large number would make simulations extremely complex. In this work, an analytical approach is developed to describe the evolution of debris clouds created by fragmentations in Low Earth Orbit. In contrast to traditional approaches, which follow the trajectory of individual fragments, with the proposed method the cloud behaviour is studied globally, so that the presence of small fragments can be modelled. This give a deeper insight into the dynamics of debris clouds and reduces the computational effort needed to estimate the consequences of a collision. A standard breakup model is used to describe the dispersion of the fragments in terms of characteristic length, area-to mass ratio and velocity. From the velocity distribution, the fragment spatial dispersion is derived. The cloud density is expressed by a continuous function that depends on the altitude and that is set as initial condition for the orbit propagation. Based on an analytical approach proposed in the literature for interplanetary dust and spacecraft swarms, the fragment cloud evolution in time is derived through the continuity equation, which is used to describe the variation of debris density considering the effect of atmospheric drag. The approach has been extended to express the cloud density as a function of multiple orbital parameters and to model additional perturbations such as the Earth’s oblateness. The method has been validated through the comparison with the traditional numerical propagation and then applied to study many breakup scenarios. The proposed approach proves to be flexible and able to study the collision risk coming from several breakup events and to evaluate the vulnerability of different targets. It is also applied to derive an index of the environmental criticality of spacecraft.

Text
Final copy for e-Prints Francesca Letizia.pdf - Other
Download (14MB)

More information

Published date: February 2016
Organisations: University of Southampton, Astronautics Group

Identifiers

Local EPrints ID: 387121
URI: http://eprints.soton.ac.uk/id/eprint/387121
PURE UUID: 8f0be52f-9e71-4e68-a287-8ab252a46919
ORCID for Camilla Colombo: ORCID iD orcid.org/0000-0001-9636-9360

Catalogue record

Date deposited: 16 Feb 2016 12:57
Last modified: 14 Dec 2018 01:42

Export record

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×