Astrochemistry

Astrochemistry comprises observations, theory and experiments aimed at interpreting molecular emission patterns in space. The chemistry of the interstellar medium strongly depends on the local density, temperature, ionization and radiation conditions and molecules with a well-understood chemistry can therefore be used as probes of astrophysical phenomena. Molecules can also regulate key aspects of star and planet formation, such as cooling and grain coagulation efficiencies. Finally, molecules such as water and organics are interesting in their own right because of the possible connection between them and origins of life. Astronomers at RG, SSP and AMP divisions carry out millimeter and infrared observations of molecules, spectroscopic and kinetic experiments, and astrochemical theory to address these broad topics.

Astronomers in the Molecular Astrophysics Laboratory are primarily engaged in the detection and spectral characterization of known or postulated molecules of astronomical interest using rotational spectroscopy. Particular emphasis is placed on the discovery of exotic or 'non-terrestrial' molecules that are generally unknown or unfamiliar on Earth, but are often quite abundant in rich astronomical sources. Examples include free radicals, carbenes, and molecular ions. Measurements in the laboratory provide highly precise rest frequencies so that radio astronomical observations, either with single dish antennas or interferometers, such as the Submillimeter-wave Array, can be undertaken with confidence. Smaller-scale efforts in atmospheric and combustion science are also being undertaken concurrently with the astronomical work because of the central role that carbon plays in all of these disciplines.