NASA Astrobiology Institute (NAI)

Molecular chemistry can provide insight into the physical processes at the earliest stages of starbirth, when molecular cloud cores collapse to form protostellar condensations. Dust particles in the dense clouds accrete molecules from the gas, resulting in the growth of ice mantles that eventually get transported into the protostellar environment. It is here, that the warm and dense environments of star forming regions promote a rich chemistry that creates complex prebiotic compounds and a small fraction of this ends up as planets. For these reasons, ice mantles in starless clouds (where harsh radiation does not affect the mantles) directly probe the dominant grain surface chemistry pathways and can be used as tracers of the origin of first generation ice molecules. This project is a comparative study of near-infrared, mid-infrared, and sub-millimeter spectral signatures of 35 discrete observations through the quiescent clouds LDN 673. Trends in the ice abundances can be studied exclusively as a function of cloud environment, such as the role of increasing extinction (dust column) in promoting grain surface chemistry.

Molecular chemistry can provide insight into the physical processes at the earliest stages of starbirth, when molecular cloud cores collapse to form protostellar condensations. Dust particles in the dense clouds accrete molecules from the gas, resulting in the growth of ice mantles that eventually get transported into the protostellar environment. It is here, that the warm and dense environments of star forming regions promote a rich chemistry that creates complex prebiotic compounds and a small fraction of this ends up as planets. For these reasons, ice mantles in starless clouds (where harsh radiation does not affect the mantles) directly probe the dominant grain surface chemistry pathways and can be used as tracers of the origin of first generation ice molecules. This project is a comparative study of near-infrared, mid-infrared, and sub-millimeter spectral signatures of 35 discrete observations through the quiescent clouds LDN 673. Trends in the ice abundances can be studied exclusively as a function of cloud environment, such as the role of increasing extinction (dust column) in promoting grain surface chemistry.