The interaction of cosmic fullerenes with their environment:confronting models with observations

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Shortly after the James Webb Space Telescope (JWST) launches on October 31st, 2021, Canadian astronomers will be among the first scientists to study the infrared (IR) Universe using the most sensitive and powerful eyes on the skies in human history. Encoded in the many breathtaking images that JWST will provide, are the fingerprints of a unique carbonaceous compound: buckyballs - a compound made of 60 carbon atoms arranged in the shape of a soccer balls. Buckyballs are the largest molecules known in space, and they are the only identified members of the "aromatic" molecules - species whose microscopic structure resembles honeycomb patterns. Aromatic molecules contain about 15% of all the carbon in the Universe. Their structure gives them "superpowers" that allow them to thrive especially well in some of the harshest, highly irradiated environments in space. In fact, they turn into productive molecular machines that efficiently convert high-energy UV radiation into lower energy infrared light, and they can also eject or capture electrons or hydrogen atoms as the conditions demand. This makes them a class of super-stable species that furthermore significantly affect their immediate surroundings by changing the radiation field and the temperature of the gas. Consequently, these microscopic particles play key roles in large-scale processes such as star formation and galaxy evolution. However, while we have seen buckyballs in many different cosmic environments, we do not know how they form, and we have an incomplete understanding of the physical processes that cause them to glow in the IR. This will change owing to observations with the JWST. Its vision is so sharp, that it can easily pinpoint precisely where buckyballs are emitting. It will also provide us with detailed information about the physical conditions at those locations as well as exquisitely detailed spectral characteristics of the buckyball's fingerprints. I will analyze those observations for different astrophysical objects, and create models to fundamentally understand the physical processes that lead to these observed spectral characteristics. Since the same processes will affect all aromatic species in space, the proposed research will lead to a much improved understanding of the cosmic organic inventory, especially in regions of star and planet formation, and of the evolution of the interstellar medium and thus the evolution of galaxies.