Description
Titan’s upper atmosphere is a key site for studying complex organic chemistry in a cold, oxygen-poor environment, with strong relevance to both planetary science and prebiotic chemistry. PAHs (Polycyclic Aromatic Hydrocarbons) have been detected there previously, but questions remain about their size, formation, and evolution. In this work, we reanalyze Cassini VIMS limb spectra using an extended version of the NASA Ames PAH IR Spectroscopic Database. We apply Monte Carlo-assisted NNLS fitting to estimate uncertainties on the spectral contributions and follow up with NNLC fitting to identify the most statistically robust PAH candidates. Preliminary results show that the average number of aromatic rings in the detected PAHs is higher than in earlier studies. Surprisingly, the largest PAHs are found at 1000 km altitude, which is counterintuitive given expected photodestruction and vertical transport. This suggests that either large PAHs are more stable than previously thought or that they are forming in situ at high altitudes. These findings challenge existing models of PAH growth and survival in Titan’s thermosphere.
| Talk category | NOVA Network 2 |
|---|---|
| Preference for a talk or poster | Poster |
