Seminar Series

Detection and characterization of transiting exoplanets: from gas giants to habitable worlds


Dr Nicolas Crouzet


Dunlap Fellow, Dunlap Institute for Astronomy and Astrophysics, University of Toronto, Candidate for the position of UC Lecturer of Astronomy

Time & Place

Mon, 13 Jun 2016 10:00:00 NZST in Rutherford 701, Level 7

All are welcome


Planets are very common in our Galaxy. Those transiting in front of their star can be studied in great detail, providing clues to their internal and atmospheric properties. I will present my work on two projects that aim at detecting and characterizing transiting planets by photometry from the ground: one targeting bright stars with a network of small telescopes located at temperate sites, and one that performs photometry from Antarctica during the continuous winter night. After their detection, these planets can be observed in spectroscopy to probe their atmospheric composition, circulation, and temperature profile.

As I will show for HD 189733b, molecular species are now detected with a high confidence level in the atmospheres of close-in gas giant exoplanets. In contrast, no spectral variations have been detected for the few known Super-Earths that can be observed with this technique; as a result, the atmospheric properties of Super-Earths and terrestrial exoplanets are yet unknown.

I will describe the chain of observations that I plan to lead in the coming years to detect terrestrial exoplanets including those in the habitable zone of their star and to characterize their atmospheres, using the synergies between the NASA TESS mission, the photometric and spectroscopic instruments at Mount John Observatory, and the SALT and JWST facilities. This research will pave the way to the search for biosignatures in the atmospheres of terrestrial planets around other stars.