Material estelar pode ser um bloco construtor na origem da vida

sábado, janeiro 26, 2019

First detection of the pre-biotic molecule glycolonitrile (HOCH2CN) in the interstellar medium

S Zeng D Quénard I Jiménez-Serra J Martín-Pintado V M Rivilla L Testi R Martín-Doménech

Monthly Notices of the Royal Astronomical Society: Letters, Volume 484, Issue 1, 21 March 2019, Pages L43–L48,

Published: 14 January 2019 

Article history Received: 06 September 2018 Revision Received: 07 January 2019 

Accepted: 07 January 2019

Image of the Rho Ophiuchi star formation region with IRAS16293-2422 B circled.
Credit: ESO/Digitized Sky Survey 2. Acknowledgement: Davide De Martin


Theories of a pre-RNA world suggest that glycolonitrile (HOCH2CN) is a key species in the process of ribonucleotide assembly, which is considered as a molecular precursor of nucleic acids. In this Letter, we report the first detection of this pre-biotic molecule in the interstellar medium by using ALMA data obtained at frequencies between 86.5 GHz and 266.5 GHz toward the Solar-type protostar IRAS16293–2422 B. A total of 15 unblended transitions of HOCH2CN were identified. Our analysis indicates the presence of a cold (Tex = 24 ± 8 K) and a warm (Tex = 158 ± 38 K) component meaning that this molecule is present in both the inner hot corino and the outer cold envelope of IRAS16293 B. The relative abundance with respect to H2 is (6.5 ± 0.6) × 10−11 and ≥(6 ± 2) × 10−10 for the warm and cold components, respectively. Our chemical modelling seems to underproduce the observed abundance for both the warm and cold component under various values of the cosmic ray ionization rate (ζ). Key gas phase routes for the formation of this molecule might be missing in our chemical network.

Keywords  line: identification, Instrumentation: interferometers, ISM: molecules, ISM: individual: IRAS16293-2422 B