New 3D model reveals complex chemistry in stellar nurseries

An international research team led by Dr. Brandt Gaches from the University of Duisburg-Essen has developed a high-resolution 3D model to illustrate the complex chemistry within stellar nurseries. The research, published in Astronomy & Astrophysics, focuses on the Orion Bar, a ridge of gas and dust in the Orion Nebula located approximately 1,350 light-years from Earth.

While previous models typically represented photodissociation regions (PDRs) as one-dimensional layers, this new model accounts for the clumpy and irregular three-dimensional structure of interstellar clouds. The model tracks how intense ultraviolet radiation from young stars interacts with molecular hydrogen, the most abundant molecule in the universe, to create shadows and alter chemical reactions.

By resolving these dense PDRs, the research helps explain how stellar feedback shapes Giant Molecular Clouds (GMCs). The findings provide a framework for interpreting observations from the James Webb Space Telescope (JWST) and the Atacama Large Millimeter/submillimeter Array (ALMA), specifically regarding how the molecular hydrogen photodissociation front overlaps with the C+ recombination front.