2021 Census of Interstellar, Circumstellar, Extragalactic, Protoplanetary Disk, and Exoplanetary Molecules

TL;DR

This paper provides a comprehensive census of 241 molecular species detected in various cosmic environments, summarizing detection methods, facilities, and spectral data, highlighting progress in astrochemistry.

Contribution

It offers the first detailed compilation and analysis of molecular detections across interstellar, circumstellar, extragalactic, protoplanetary, and exoplanetary environments, including detection details and visual data representations.

Findings

241 molecules detected across diverse environments

Detection methods span from cm-wavelengths to ultraviolet

Includes tentative and disputed detections

Abstract

To date, 241 individual molecular species, comprised of 19 different elements, have been detected in the interstellar and circumstellar medium by astronomical observations. These molecules range in size from two atoms to seventy, and have been detected across the electromagnetic spectrum from cm-wavelengths to the ultraviolet. This census presents a summary of the first detection of each molecular species, including the observational facility, wavelength range, transitions, and enabling laboratory spectroscopic work, as well as listing tentative and disputed detections. Tables of molecules detected in interstellar ices, external galaxies, protoplanetary disks, and exoplanetary atmospheres are provided. A number of visual representations of this aggregate data are presented and briefly discussed in context.