Use this URL to cite or link to this record in EThOS:
Title: A multi-dataset analysis of the dynamics of Saturn's magnetic field configuration
Author: Davies, Ewen
ISNI:       0000 0004 9357 0749
Awarding Body: Imperial College London
Current Institution: Imperial College London
Date of Award: 2019
Availability of Full Text:
Access from EThOS:
Access from Institution:
The planet Saturn is the second largest planet in the solar system. It is a magnetised body, surrounded by a magnetosphere which acts as a cavity within the solar wind. The Cassini spacecraft explored this system for 13 years, from 2004 until 2017, seeking to answer many of the outstanding questions about this unique solar system environment. This thesis examines a small part of the answer to one of those questions: To what extent are the dynamics of Saturn’s magnetosphere driven by internal and external factors? Saturn’s dayside magnetic field azimuthal configuration is found to exhibit a swept-back configuration at dawn and throughout the dayside, until the early afternoon where it becomes swept-forward. This is found to be similar to the Jovian configuration, although with an earlier boundary. The configuration is shown not to vary significantly with Saturn’s seasons, although some variation is shown to exist. This background having been established, transient events in the configuration can be examined. A case study is carried out on a series of orbits that carry the spacecraft through the high latitude pre-dusk region. These orbits are examined for transient changes as a result of solar wind shocks, the arrival of which is modelled by the Michigan Solar Wind Model. Such transients are detected in 2 of 3 cases, suggesting a solar wind influence on the transient behaviour of the field configuration. To study internal influences of the system, a survey of the post-dawn sector is carried out for transient changes in the configuration that would indicate the presence of return flow plasma, resulting from tail reconnection. 33 instances are detected, characterised by field and particle signatures. These events are found to exhibit organisation by planetary period oscillation phase, suggesting a degree of control on tail reconnection by the rotation of the planet.
Supervisor: Masters, Adam ; Dougherty, Michele Sponsor: Science and Technology Facilities Council
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral