Institute of Astronomy

- Ryan MacDonald


Office: Hoyle H27
Office Tel: (01223) 766653
More Info (Internal)


Research Themes: Star Formation and Exoplanets

Research Keywords: Planets, Spectroscopy, Theory


My research focuses on the atmospheric characterisation of transiting extrasolar planets. I work with Dr Nikku Madhusudhan to develop new atmospheric retrieval tools to extract the atmospheric properties (chemical composition, temperature, clouds etc.) of exoplanets.

Research highlights


  • First conclusive detection of titanium oxide (TiO) in an exoplanetary atmosphere.
  • First evidence of nitrogen chemistry (NH3 / HCN) in hot Jupiter exoplanets.

Selected papers

  1. MacDonald, R.J., Marley, M.S., Fortney, J.J., & Lewis N.K., 2018, 'Exploring H2O Prominence in Reflection Spectra of Cool Giant Planets' - ApJ 858, 69
  2. MacDonald, R.J. & Madhusudhan, N., 2017, 'Signatures of Nitrogen Chemistry in Hot Jupiter Atmospheres' - ApJL 850, L15
  3. Sedaghati, E., Boffin, H.M.J., MacDonald, R.J., et al., 2017, 'Detection of titanium oxide in the atmosphere of a hot Jupiter' - Nature 549, 238
  4. MacDonald, R.J. & Madhusudhan, N., 2017, 'HD 209458b in New Light: Evidence of Nitrogen Chemistry, Patchy Clouds and Sub-Solar Water'MNRAS 469, 1979


2015-Present: PhD in Astronomy (Cambridge)

Supervisor: Dr Nikku Madhusudhan

Project: Inverse Modelling Methods for the Characterisation of Exoplanetary Atmospheres

2016: Kavli Summer Program in Astrophysics Fellow (UC Santa Cruz)

Supervisor: Dr Mark S. Marley

Project: Water Absorption Signatures in Cool Giant Planets

2015: Masters Research Student (Oxford)

Supervisors: Dr Neil Bowles & Dr Kerri Donaldson Hanna

Project: Phobos Sample Return via Thermal-IR Profiling

2014: Venus Express Data Analyst (Oxford)

Supervisor: Dr Colin Wilson

Project: Correlations Between Temperature Structure and UV Contrasts in the Clouds of Venus



PhD, Astronomy - University of Cambridge (2015-present)

MPhys, Physics (1st Class) - University of Oxford (2011-2015)

Awards and Prizes

2017: Paul Murdin Prize - Best published journal paper produced by a current Cambridge Institute of Astronomy Ph.D. student (joint award).

Page last updated: 7 May 2018 at 17:04