Supervisory Team: Hugh Lewis (SoE), Daniel Whiter (P&A), Robert Fear (P&A)
Project description
In this project you will investigate how variable heating of the upper atmosphere by the aurora affects the orbits and re-entry of spacecraft in low Earth orbit, with the aim of improving orbit prediction.
As society becomes increasingly reliant on space technology, it is increasingly important to understand the variability of the upper atmosphere and environment in which spacecraft operate. 2020 saw the largest annual increase in operational spacecraft, mainly in low Earth orbit, a trend set to continue with the rapid growth of commercial megaconstellations. Correspondingly, the frequency of collision near misses is also increasing, making accurate orbit prediction vital. The temperature of the upper atmosphere is highly variable, particularly in the polar regions where aurora can cause intense localised heating. Changes in temperature link to changes in neutral density, and so changes in the drag experienced by spacecraft. Accurate orbit prediction therefore relies on knowing how the atmospheric temperature responds to space weather events. However, monitoring the temperature during dynamic events is challenging; spacecraft can provide only short snippets of information as they rapidly pass overhead, and models cannot yet reproduce short term variability.
The University of Southampton operates a high-resolution auroral spectrograph on the Arctic archipelago of Svalbard. Our previous work using the spectrograph has shown that the ratio of intensities of two auroral O+ emission lines does not match earlier theories for the ionisation-excitation of O+. The proposed explanation is that conservation of angular momentum limits the allowed change in quantum numbers as neutral O is ionised to O+ by electron impact, with the exciting implication that it would be possible to remotely measure neutral temperature at 250 km altitude throughout an auroral event.
In this project you will validate the new technique for measuring temperature and use such measurements together with modelling to improve forecasts of drag on spacecraft. Polar orbit predictions, for example during spacecraft re-entry, will be tested. The project blends a diverse range of research fields, including space science, astronautics, computational modelling, atomic physics and observational physics.
The project is part of the University of Southampton's Centre of Excellence for In situ and Remote Intelligent Sensing (IRIS). You will be a member of both the Astronautics group in the School of Engineering and the Space Environment Physics group in the School of Physics and Astronomy, with participation in both groups' meetings and seminar series. The PhD will include travel to national and international conferences, as well as the possibility to join fieldwork expeditions to Svalbard, for which training will be provided.
Entry Requirements
A very good undergraduate degree (at least a UK 2:1 honours degree, or its international equivalent) in Physics, Engineering or related subject.
Closing date: 27 May 2022.
Funding: For UK students, Tuition Fees and a stipend of £15,609 tax-free per annum for up to 3.5 years.
How To Apply
Apply online https://www.southampton.ac.uk/courses/how-to-apply/postgraduate-applications.page. Select programme type (Research), 2022/23, Faculty of Physical Sciences and Engineering, next page select “PhD Engineering & Environment (Full time)”. In Section 2 of the application form you should insert the name of the supervisor Hugh Lewis
Applications should include:
Curriculum Vitae
Two reference letters
Degree Transcripts to date
For further information please contact: [Email Address Removed]
Continue with Facebook
