Molecular astrophysics is an interdisciplinary research field that focuses on the study of chemical reactions in astrophysical environments. Chemistry plays a fundamental role in the evolution of galaxies, stars and the interstellar medium, for example in the composition of the gas, the formation of solid particles, the ionisation structure, temperature and density of astrophysical objects and ultimately, the origin of life.
The main methods by which the chemistry of space is studied are 1) spectroscopic observations of astrophysical objects, utilising the entire electromagnetic spectrum from radio to X-ray wavelengths, 2) laboratory analysis of chemical species and reactions, and 3) theoretical calculations and computer modelling of astrophysical environments and chemical reactions.
The group at Queen's University Belfast is led by Prof. Tom Millar. Our current emphasis is on the modelling of astrochemical processes in various envrionments (including dark, quiescent molecular clouds, carbon-rich circumstellar envelopes and protoplanetary discs), to build understanding of the molecular evolution of the universe from clouds of gas to stars and ultimately planets. Subsequent microwave observations of molecules in space allow us to test our models, refine theories and generate further knowledge about the physics and chemistry of space.
The image to the right shows the Orion Nebula, located in Orion's sword, a nearby (1500 light years distant) region of active star formation, home to over 1000 young stars. This image was taken by the Hubble Space Telescope and reveals vast clouds of gas and dust, illuminated and heated predominantly by the four massive stars in the centre. The dark, dense clouds that can be seen are where stars begin to form and are host to a rich organic chemistry. Molecules are rapidly destroyed and remade in the illuminated regions where ultraviolet photons dominate the chemistry.