Discovery of the interstellar chiral molecule propylene oxide (CH ₃ CHCH ₂ O)

Abstract

Life on Earth relies on chiral molecules-that is, species not superimposable on their mirror images. This manifests itself in the selection of a single molecular handedness, or homochirality, across the biosphere. We present the astronomical detection of a chiral molecule, propylene oxide (CH3CHCH2O), in absorption toward the Galactic center. Propylene oxide is detected in the gas phase in a cold, extended molecular shell around the embedded, massive protostellar clusters in the Sagittarius B2 star-forming region. This material is representative of the earliest stage of solar system evolution in which a chiral molecule has been found.

Formation of Glycerol through Hydrogenation of CO Ice under Prestellar Core Conditions

“…With the increasing sensitivity of astronomical observing facilities, more and more complex organic molecules (COMs) have been identified in space (Halfen et al 2015;Cernicharo et al 2016;Jørgensen et al 2016;McGuire et al 2016). Gasphase reactions are not efficient enough to explain many of the observed COM abundances, and it is generally accepted that such species form on the surfaces of icy dust grains by merging smaller species to larger and larger constituents.…”

Mechanically Induced Homochirality in Nucleated Enantioselective Polymerization

“…1 A key question in this context is the relationship of the polymerization process with the emergence of chirality. This question has spurred recent activity devoted to modeling efforts aimed at understanding mirror symmetry breaking and chiral amplification in chiral polymerization of potential relevance to the origin of life.…”

Submillimeter spectra of 2-hydroxyacetonitrile (glycolonitrile; HOCH2CN) and its searches in GBT PRIMOS observations of Sgr B2(N)

“…We do not, however, make the assumption that this temperature is described by local thermodynamic equilibrium (LTE), meaning that the excitation temperature is not thermalized to the kinetic temperature of the gas. This approach has previously proven to be successful in modeling both the emission and absorption of molecules in PRIMOS observations (Hollis et al 2004;Loomis et al 2013;McGuire et al 2016). We note, however, that several other molecules exhibit populations which cannot be described by a single excitation temperature (McGuire et al 2012;Faure et al 2014), and thus care should be taken to examine any single-excitation temperature results on a case-by-case basis.…”