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


Percentage of known molecules that were detected for the first time in carbon stars, dark clouds, LOS clouds, and SFRs (see text). Some molecules were simultaneously detected in multiple source types (e.g., C8H – in TMC-1 and IRC+10216).

To date, 240 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.

Brett A. McGuire

Comments: Accepted for publication in the Astrophysical Journal Supplements. Corrections and comments are strongly encouraged and *extremely* appreciated. See also this https URL
Subjects: Astrophysics of Galaxies (astro-ph.GA)
Cite as: arXiv:2109.13848 [astro-ph.GA] (or arXiv:2109.13848v1 [astro-ph.GA] for this version)
Submission history
From: Brett McGuire
[v1] Mon, 27 Sep 2021 17:07:09 UTC (2,647 KB)
https://arxiv.org/abs/2109.13848
Astrobiology, Astrochemistry,

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