Characterising the atmospheres and interiors of extrasolar planets
My research focuses on atmospheric and interior modeling of exoplanets. My overall research goal is to use the wealth of observations at our disposal to better understand the exoplanet population and put our Solar System in context.
I am currently a 51 Pegasi b Postdoctoral Fellow in the School of Earth and Space Exploration at Arizona State University, and a member of the Exoteric Lab. I was previously a postdoctoral researcher in the Astronomy department at the University of Maryland. I completed my PhD at the Institute of Astronomy, University of Cambridge. My PhD thesis can be accessed here.
If you're interested in any of my research topics listed below, feel free to get in touch at matthewnixon[at]asu.edu.
I maintain a spreadsheet of JWST transiting exoplanet observations, which can be accessed here. Let me know if you publish some observations I should include, or if you notice anything I've missed.
Deciphering sub-Neptunes through joint atmospheric-interior characterisation
Planets larger than Earth, but smaller than Neptune, are common in the Galaxy despite being absent from the Solar System. My research aims to better understand the structure, formation and evolution of these mysterious planets by building models that link their observable atmospheres to processes occurring in the deep interior
Using three-dimensional structure to reveal the climates of giant exoplanets
New observatories such as JWST and high-resolution ground-based facilities are providing evidence of three-dimensional inhomogeneity across the atmospheres of giant irradiated exoplanets. My work involves developing new techniques that can leverage these observations to gain insight into the climate and dynamics of these worlds.
Building the next-generation toolkit for exoplanet atmospheres
My research also explores the need for advanced statistical and computational methods when interpreting state-of-the-art exoplanet observations, particularly as we push towards characterising small planets that test the limits of our facilities.
• Standing on a sub-Neptune. AAS Nova, 2025
• New study revises our picture of the most common types of planets in the galaxy. ASU press release, 2025
• Claim of alien life on distant world meets swift scientific pushback. AAAS Science news article, 2025.
• Hopes for alien life dim as doubts emerge over exoplanet K2-18b chemical signals. Phys.org, 2025
• Hoe sterk is ‘het beste bewijs voor buitenaards leven’? (How strong is ‘the best evidence for extraterrestrial life’?) Trouw, 2025
• New Studies Dismiss Signs of Life on Distant Planet. New York Times, 2025
• Astronomers Detect a Possible Signature of Life on a Distant Planet. New York Times, commentary (not involved in study), 2025
• Eight Post-Doctoral Scientists Awarded 51 Pegasi b Fellowship. Heising-Simons Foundation press release, 2025
• ASU to host 2 new 51 Pegasi b Fellows, cementing leadership in exoplanet research. ASU press release, 2025
• NASA’s Webb Lifts Veil on Common but Mysterious Type of Exoplanet. NASA press release, 2025
• Researchers Measure the Light Emitted by a Sub-Neptune Planet’s Atmosphere for the First Time. University of Maryland press release, 2023
• NASA’s Webb Takes Closest Look Yet at Mysterious Planet. NASA press release, 2023
• NASA’s Webb Reveals an Exoplanet Atmosphere as Never Seen Before. NASA press release, 2022
• NASA’s Webb Detects Carbon Dioxide in Exoplanet Atmosphere. NASA press release, 2022
• How deep is an exoplanet's ocean? Astrobites, 2021
• Machine learning can help decode alien skies, up to a point. Eos, American Geophysical Union, 2020
• Potentially habitable exoplanet could broaden the search for life beyond Earth. CNN, 2020
• Large exoplanet could have the right conditions for life. University of Cambridge press release, 2020
Header image credit: Hailey Nelson