Analysing the atmospheres of exoplanets needs knowledge of the molecules they are made up of. University College London’s Professor Jonathan Tennyson is working on the ExoMol project to do just that. We talk to him about his work.
Q: Which research projects are you and your group currently working on?
We are working on a number of projects but the main one is ExoMol: molecular line lists for exoplanet and other atmospheres. The purpose of this project is to make spectroscopic models for molecules which are known to be or likely to be constituents of the atmospheres of planets orbiting other stars. The resulting comprehensive lists of transitions are vital for interpreting spectra from these objects and other hot bodies such as brown dwarfs and, indeed, for a variety of terrestrial applications such as the monitoring of flue gases.
Q: What motivated you to pursue this field of research?
The project was motivated by the need for comprehensive line lists for hot bodies, particularly exoplanets. Such line lists can contains billions of transitions and are thus not amenable to direct experimental measurement.
Q: Where do you think the field is heading?
For my group we are heading to bigger molecules but the real issue in exoplanet characterisation is the lack of high quality observational data. Such observations are difficult and a purpose-built space mission is urgently needed to make significant progress in understanding what these faraway worlds are made of.
Q: What do you consider to be the hot topics in Atomic, Molecular and Optical (AMO) physics at the moment?
We are living in exciting times for AMO physics with many hot topics ranging from quantum information, use of ultrafast lasers to control matter on very short times scales and the whole field of ultracold physics. At a personal level I am intrigued by the possibilities raised by ultracold chemistry.
Q: What current problem facing humanity would you like science to provide a solution to?
I would say climate change is biggest single issue facing humanity. There is clearly need for scientific solutions at several levels from green energy generation and storage, to measures to help mediate against the worst effects of climate change. My group is involved trying to make the spectroscopic data used in atmospheric research as robust as possible and, for example, our recent calculations on carbon dioxide should prove important in helping to determine both sources and sinks of CO2 in our atmosphere. We are also contributing to fusion-related research.
Q: What has been the most exciting development in physics during the course of your career?
There have been many: Bose-Einstein condensation and the use of lasers to make ultracold matter and the whole area of quantum information are game-changing developments in AMO physics. Personally I am really excited by the whole area of exoplanet science and feel privileged to be working at a time when this field started.
On behalf of JPhysB I would like to thank Professor Tennyson for answering our questions and for recently publishing “R-matrix calculation of bound and resonant states of BeH” in our journal.
- An R-matrix study of singlet and triplet continuum states of N2.
- Theoretical methods for small-molecule ro-vibrational spectroscopy.
- Professor Tennyson has also written a book on these subjects: Astronomical Spectroscopy, An Introduction to the Atomic and Molecular Physics of Astronomical Spectra, now in its second edition.
- There is also a fascinating podcast on ExoMol and exoplanet spectroscopy which you can listen to at Pod Academy.
This work is licensed under a Creative Commons Attribution 3.0 Unported License
Image 1: copyright Jonathan Tennyson; used with permission.