Probing the Chemical Complexity of Interstellar Ices

Summary

Meteorites and comets are proposed to have delivered much of Earth's water, and probably large abundances of organic molecules, critical for the emergence of life. Theory and laboratory ice experiments both suggest that these organics originally formed in the icy mantles of interstellar dust grains. Direct observations of organics in ices are however not possible and current estimations, based on gas-phase observation of thermally sublimated ice suffer, from contamination by gas-phase reactions.
As an alternative to thermal sublimation, energetic particles such as photons, electrons, atoms, and cosmic-rays, can ablate some of the ice mantle, providing a reliable gas-phase fingerprint of the ice composition. To realize the use of such fingerprints as a quantitative tool to measure ice compositions, I will experimentally characterize the non-thermal sublimation efficiencies and pathways of three interstellar ice constituents - CO, CH3OH and CH3OCH3 - selected as templates of inorganic, simple organic, and complex organic ice components. The experiments will be used together with astrochemical theory to predict the gas-phase abundance patterns of these molecules in different interstellar environments, and these predictions will be tested against spatially resolved millimeter observations from the Submillimeter Array.

Output

Scientific article

Details

Project number

680-50-1302

Main applicant

Dr. E.C. Fayolle

Affiliated with

Universiteit Leiden, Faculteit der Wiskunde en Natuurwetenschappen, Sterrewacht Leiden

Team members

Dr. E.C. Fayolle

Duration

03/02/2014 to 29/01/2016