Astrochemistry articles from across Nature Portfolio

The abiotic production of molecular oxygen in carbon dioxide-rich planetary atmospheres is important in understanding astrochemical reactions and potentially the origin of life on Earth. Here, the authors demonstrate that the low-energy reaction between helium ions, as found in solar winds, and carbon dioxide produces molecular oxygen.

CO₂ is prominent in the Earth’s and exoplanetary atmospheres, but its excited state photochemistry is not yet fully understood. Here the authors identify gradual quenching of the diffuse vibrational structure in supercritical CO₂ electronic spectra under pressures up to 137 bar.

Cyanide anions exist in interstellar space, but the vibrationally or electronically excited states above the electron autodetachment threshold of CN^- are assumed to have no contributions to cosmic CN^-. Here, the authors report long-lived, superexcited CN^- from the dissociative electron attachment to cyanogen bromide.

H₃⁺ has great astronomical significance, but its formation mechanisms are not fully understood. Here a combined experimental and theoretical study of H₃⁺ formation dynamics from ethane dications shows that roaming occurs at a much longer timescale than the transition state, and is accompanied by nuclear motion of larger amplitudes.

The size distribution of solid grains in dense clouds is a key parameter to constrain in order to understand grain growth, which influences the nature and timescale of the formation of protoplanets. A JWST study has quantified the grain size distribution by modelling the spectral absorptions arising from ice components of grains before protostellar collapse.

In the interstellar medium, complex organic molecules are believed to form on icy dust grains in dark molecular clouds. Research now shows that carbon atoms, previously considered immobile, can diffuse across ice surfaces to take part in reactions with other adsorbed species.

A nearby galaxy provides a clue for resolving a long-standing issue in the way we measure elemental abundances from spectra, setting the stage for better interpreting the chemical evolution of galaxies across different cosmic epochs.