Irwin, Professor Patrick

Websites 

Departmental website 

Personal research site 

Teaching 

Undergraduate: Currently 1^st Year Maths, 2^nd Year Optics

Graduate: DPhil Supervision

Academic background and research interests

Patrick Irwin is an academic in the sub-department of Atmospheric, Oceanic, and Planetary Physics, working on remote sensing of planetary atmospheres. He is, or has been, a co-investigator or team member on the following space instruments: Galileo/NIMS, Cassini/CIRS, Venus Express/VIRTIS, Rosetta/VIRTIS and Mars Reconnaissance Orbiter/MCS. In addition to spacecraft observations, he is also involved with ground-based and space-based telescope observations of the giant planets and has taken a particular interest in monitoring the changes in Uranus’s cloud structure and colour during and after its northern spring equinox in December 2007, studying the atmosphere of Neptune, and making ground-based observations of Jupiter in support of the NASA Juno mission. He made the first ever unambiguous detection of hydrogen sulphide in the atmospheres of Uranus and Neptune, made the first ground-based detection of a dark spot in Neptune’s atmosphere, and made the first ever spectral characterisation of such a spot. He has also modelled the visible colours of the planets, and made a new estimate of the power budget of Uranus, showing that it is not in thermal equilibrium with the incident sunlight, but actually has a significant internal heat source. Most recently he has turned his attention to Jupiter and has been observing and modelling the abundance of clouds and ammonia in preparation for the arrival of ESA’s JUICE spacecraft at Jupiter in 2031, carrying the MAJIS instrument, on which Patrick is a co-investigator.

Publications:

Books:

Irwin, P.G.J., Giant planets of our solar system: Atmosphere, compositions and structure, Springer-Praxis, 2003.

Irwin, P.G.J., Detection methods and properties of known exoplanets, in Exoplanets (ed. J.W. Mason), Springer-Praxis, 2008.

Irwin, P.G.J., Giant planets of our solar system: Atmosphere, compositions and structure – 2nd Edition, Springer-Praxis, 2009.

Papers:

Patrick Irwin is the principal author or co-author on over 300 papers in the scientific literature. A selection of papers is listed below.

1. Irwin, P.G.J., N.A. Teanby, R. de Kok, L.N. Fletcher, C.J.A. Howett, C.C.C. Tsang, C.F. Wilson, S.B. Calcutt, C.A. Nixon, P.D. Parrish (2008). The NEMESIS planetary atmosphere radiative transfer and retrieval tool,  Quant. Spectrosc. and Rad. Trans., 109, 1136 – 1150. doi:10.1016/j.jqsrt.2007.11.006.
2. Irwin, P. G. J., Toledo, D., Garland, R., Teanby, N. A., Fletcher, L. N., Orton, G. A., & Bézard, B. (2018). Detection of hydrogen sulfide above the clouds in Uranus’s atmosphere. Nature Astronomy, 2, 420-427. doi:1038/s41550-018-0432-1
3. Irwin, P. G. J., Toledo, D., Garland, R., Teanby, N. A., Fletcher, L. N., Orton, G. A., & Bézard, B. (2019). Probable detection of hydrogen sulphide (H2S) above the clouds in Neptune’s atmosphere. Icarus, 321, 550-563. doi:10.1016/j.icarus.2018.12.014
4. Irwin, P.G.J., Parmentier, V., Taylor, J., Aigrain, S., Lee, G.K., & Garland, R. (2020). 2.5-D retrieval of atmospheric properties from exoplanet phase curves: Application to WASP-43b observations. MNRAS 493,106-125. doi:10.1093/mnras/staa238
5. Irwin, P.G.J. et al. (2022) Hazy Blue Worlds: A Holistic Aerosol Model for Uranus and Neptune, Including Dark Spots. JGR-Planets 127. 10.1029/2022JE007189.
6. Irwin, P.G.J. et al. (2023) Spectral determination of the colour and vertical structure of dark spots in Neptune’s atmosphere. Nature Astronomy 7, 1198–1207. 10.1038/s41550-023-02047-0
7. Irwin, P.G.J. et al. (2023) Latitudinal Variations in Methane Abundance, Aerosol Opacity and Aerosol Scattering Efficiency in Neptune’s Atmosphere Determined From VLT/MUSE. JGR-Planets 128. 10.1029/2023JE007980.
8. Irwin, P.G.J. et al. (2024) Modelling the seasonal cycle of Uranus’s colour and magnitude, and comparison with Neptune. MNRAS 527, 11521–11538. 10.1093/mnras/stad3761.
9. Irwin, P.G.J., Wenkert, D., Simon, A., Dahl, E., Hammel. H. (2025) The bolometric Bond albedo and energy balance of Uranus. MNRAS. 10.1093/mnras/staf800.1093/mnras/staf800
10. Irwin, P.G.J., Hill, S.M., Fletcher, L.N., Alexander, C., Rogers, J.H. (2025) Clouds and ammonia in the atmospheres of Jupiter and Saturn determined from a band-depth analysis of VLT/MUSE observations. JGR-Planets 130. 10.1029/2024JE008622.