Speaker
Description
The origins of life on Earth is postulated to have begun with simple organic molecules. A plausible source of such prebiotic molecules is the interstellar medium (ISM). Therefore, the search for complex organic molecules (COMs, containing C and more than 6 atoms) especially nitrogen-bearing prebiotic molecules in the ISM has opened the possibility of understanding how life could emerge on Earth.
G+0.693, the quiescent giant molecular cloud located in the Galactic Centre (GC) is a prolific repository of large organic species observed in the ISM. Although this region has shown no signatures of star formation, it presents almost the same level of chemical complexity as that found in the star-forming cluster Sagittarius B2(N). In order to explore the complexity of organic species in this source, and more importantly, to understand the synthesis of these interstellar COMs, we performed a spectral line survey toward this GC cloud with the IRAM-30m telescope and the GBT telescope. In total, 17 nitrogen-bearing species including several prebiotic molecules such as isocyanic acid (HNCO), formamide (NH2CHO) and methyl isocyanate (CH3NCO) have been conclusively identified. With no doubt, these molecules are chemically relevant to the formation of the building blocks of life due to their peptide-like structure i.e. the important linkage between amino acids to form proteins. We will present the molecular abundance with respect to H2 of the detected species and the abundance ratio between relative species. A comparison with observation across various astrophysical environments will also be discussed. The Galactic Centre is a harsh environment where molecular clouds are exposed to energetic phenomena such as intense UV radiation fields, enhanced cosmic ionization rates and shock waves. The detection of such high chemical complexity in this cloud demonstrates that complex organics can survive even in the harshest and most extreme environments.
