The chemical composition of a comet nucleus can be very strictly constrained by combining the latest results on: the core-mantle interstellar dustmodel, the solar systemabundances of the elements, the space observed composition of the dust of comet Halley, and the latest data on the volatile molecules of comet comae. The distribution of the components in the comet nucleus fall naturally into tw...

Measurements by dust detectors on interplanetary spacecraft appear to indicate a substantial flux of interstellar particles with masses > 10−12 g. The reported abundance of these massive grains cannot be typical of interstellar gas: it is incompatible with both interstellar elemental abundances and the observed extinction properties of the interstellar dust population. We discuss the likelihood...

NASA’s Interstellar Probe Mission will be the first spacecraft specifically designed to explore the outer solar system, pass through the boundaries of the heliosphere, and sample the nearby interstellar medium. During the spring of 1999, NASA’s Interstellar Probe Science and Technology Definition Team* developed a concept for a mission that will travel to 200400 AU using solar-sail propulsion. ...

Benzonitrile (c-C6H5CN, where ‘c’ indicates a cyclic structure), polar proxy for benzene (c-C6H6), has the potential to serve as highly convenient radio probe aromatic chemistry, provided that this ring can be found in other astronomical sources beyond molecule-rich prestellar cloud TMC-1. Here we present evidence of benzonitrile four prestellar, and possibly protostellar, sources: Serpens 1A, ...

The hypothesis that the cyanomethyl anion CH2CN is responsible for the relatively narrow diffuse interstellar band (DIB) at 8037.8± 0.15 Å is examined with reference to new observational data. The 00 absorption band arising from the B1 − X̃ 1A′ transition from the electronic ground state to the first dipole-bound state of the anion is calculated for a rotational temperature of 2.7 K using litera...

Acetamide (CH3CONH2) has been detected in emission and absorption toward the star-forming region Sagittarius B2(N) with the 100 m Green Bank Telescope (GBT) by means of four A-species and four E-species rotational transitions. All transitions have energy levels less than 10 K. The Sgr B2(N) cloud is known to have a cold halo with clumps of gas at several different velocities. Absorption feature...

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 co...

Pure acetonitrile (CH3CN) and mixed CO:CH3CN H2O:CH3CN ices have been irradiated at 15K with Vacuum UltraViolet (VUV) photons in the 7-13.6 eV range using synchrotron radiation. VUV photodesorption yields of CH3CN photo-products derived as a function incident photon energy. The coadsorption CO H2O molecules, which are expected to be among main constituents interstellar ices, is found no signifi...

2-aminooxazole (2AO), a N-heterocyclic molecule, has been proposed as an intermediate in prebiotic syntheses. It demonstrated that it can be synthesized from small molecules such cyanamide and glycoaldehyde, which are present interstellar space. The aim of this work is to provide infrared spectra, the solid phase for conditions typical astrophysical environments estimate its stability toward UV...

We present the experimental InfraRed Multiple Photon Dissociation (IRMPD) spectrum and fragmentation mass of irregular, cationic PAH dibenzo[a,l]pyrene (C24H14+) in 6–40?m/250–1650 cm?1 range. The use Free-Electron Laser for IntraCavity Experiments (FELICE) enabled us to record its Far-InfraRed (FIR) first time. aim understand how irregularity affects infrared chemistry PAHs. Dibenzo[a,l]pyrene...