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Project Progress

Co-Investigator Murthy Gudipati along with Co-Investigator Robert West in collaboration with Benjamin Fleury, Nathalie Carrasco, and Isabelle Couturier have continued investigations of the evolution of complex organic species in astrobiologically significant regions on Titan’s surface. They investigated the oxygenation chemistry involving the condensed Titan’s organic aerosols with water-ice on Titan’s surface—induced by high energy photons simulating the cosmic ray induced chemistry on Titan’s surface.

Laboratory work focused on surface chemistry simulations. Their results in longer wavelength photochemistry of C₄N₂ ice prompted reexamination of UV-VIS light reaching Titan’s surface, measured by Huygens probe, showing that the flux of >350 nm light reaching Titan’s surface is not insignificant. Based on these ideas, they focused experiments more towards understanding longer wavelength photochemical activity of Titan’s surface organic simulants.

The following experiments were performed: (1) Longer wavelength photochemistry of H₂O/C₄N₂ ice mixtures (surface processes) and (2) Vacuum ultraviolet (VUV – Lyα at 121.6 nm) irradiation of H₂O/C₄N₂ ice mixtures to simulate cosmic ray induced chemistry on Titan’s surface and near subsurface, where water and organic matter coexist.

The data is being analyzed at present. Preliminary results indicate that photochemical activity is seen in all the above cases, with varying degrees of efficiency. While VUV irradiation resulted in extensive photochemical processing, longer wavelength photochemistry was slow.