Discovery of the Interstellar Chiral Molecule Propylene Oxide   (CH$_3$CHCH$_2$O)
  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 (CH$_3$CHCH$_2$O), 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. 
Brett A. McGuire and P. Brandon Carroll, Ryan A. Loomis, Ian A.   Finneran, Philip R. Jewell, Anthony J. Remijan, Geoffrey A...
astro-ph.GA