On October 29, 2015, Prof. Alain Omont from the Institut d'astrophysique de Paris visited NAOC and gave a lecture about how astronomers study fullerenes.
He started by explaining that fullerenes are large molecules made of carbon which are approximately spherical or cubical in shape. The most famous example of a fullerene is C60 which has the shape of a ball made out of pentagonal arrangements of carbon. Prof. Omont continued by showing a crowded molecular spectrum of C60 and explaining how these spectra form a diffuse interstellar band. In addition, he showed diagrams of fullerenes that had various sizes and shapes and gave an overview of the spectroscopic energy levels associated with fullerenes. He also described how these molecules were first identified in astronomical observations in 1993 and subsequently astronomers have found many kinds of fullerenes like C70 in planetary nebulae and reflection nebulae in the Milky Way and Magellanic Clouds. Prof. Omont also explained that these structures have been identified with data from the Spitzer spacecraft in mid-infrared in 2010, and that astronomers are still searching for them in astronomical observations. He discussed aspects of fullerene chemistry that occur in the interstellar medium, highlighting their formation and growth as well as their destruction and decay. Prof. Omont ended his talk by discussing how various atoms can be encapsulated inside a fullerene and that this is an ongoing field of research that astronomers and spectroscopists are pursuing with more laboratory experiments and improved astronomical data.