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

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.

Accepted for publication in the Astrophysical Journal Supplements. Corrections and comments are strongly encouraged and extremely appreciated. See also https://github.com/bmcguir2/astromol. V2: Minor typo corrections and moved n-methylformamide to its rightful place in the detected section. arXiv admin note: substantial text overlap with arXiv:1809.09132

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Cited by in corpus (99)

• Discovery in space of ethanolamine, the simplest phospholipid head group
• Reactivity of HCO with CH3 and NH2 on Water Ice Surfaces. A Comprehensive Accurate Quantum Chemistry Study
• Aromatics and Cyclic Molecules in Molecular Clouds: A New Dimension of Interstellar Organic Chemistry
• A Search for Heterocycles in GOTHAM Observations of TMC-1
• LIDA - The Leiden Ice Database for Astrochemistry
• Discovery of the elusive carbonic acid (HOCOOH) in space
• Carbon-Chain Chemistry in the Interstellar Medium
• N-bearing complex organics toward high-mass protostars: Constant ratios pointing to formation in similar pre-stellar conditions across a large mass range
• CoCCoA: Complex Chemistry in hot Cores with ALMA. Selected oxygen-bearing species
• An overview of desorption parameters of Volatile and Complex Organic Molecules: A systematic dig on experimental literature
• The Role of Acetylene in the Chemical Evolution of Carbon Complexity
• The ALMA-PILS survey: First tentative detection of 3-hydroxypropenal (HOCHCHCHO) in the interstellar medium and chemical modeling of the C${}_3$H${}_4$O${}_2$ isomers
• Resolving desorption of complex organic molecules in a hot core: Transition from non-thermal to thermal desorption or two-step thermal desorption?
• Infrared spectra of complex organic molecules in astronomically relevant ice mixtures. V. Methyl cyanide (acetonitrile)
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• Radical Addition and H Abstraction Reactions in C2H2, C2H4 and C2H6: A Gateway for Ethyl and Vinyl Bearing Molecules in the Interstellar Medium
• The GRETOBAPE gas-phase reaction network: the importance of being exothermic
• ALMA-IMF XI: The sample of hot core candidates A rich population of young high-mass proto-stars unveiled by the emission of methyl formate
• Formation of S-bearing complex organic molecules in interstellar clouds via ice reactions with C2H2, HS, and atomic H
• Complex organic molecules detected in twelve high-mass star-forming regions with Atacama Large Millimeter/submillimeter Array (ALMA)
• Investigating Anomalous Photochemistry in the Inner Wind of IRC+10216 Through Interferometric Observations of HC${}_3$N
• HyGAL: Characterizing the Galactic ISM with observations of hydrides and other small molecules -- I. Survey description and a first look toward W3(OH), W3 IRS5 and NGC 7538 IRS1
• Shocking Sgr B2(N1) with its own outflow: A new perspective on segregation between O- and N-bearing molecules
• Oxygen-bearing organic molecules in comet 67P's dusty coma: first evidence for abundant heterocycles
• Infrared free-electron laser irradiation of carbon dioxide ice
• Cold CAS Ion Trap -- 22 pole trap with ring electrodes for astrochemistry
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• Sensitivity Analysis of Aromatic Chemistry to Gas-Phase Kinetics in a Dark Molecular Cloud Model
• Radial and vertical constraints on the icy origin of H${}_2$CO in the HD 163296 Protoplanetary Disk
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• SO2 and OCS toward high-mass protostars: A comparative study between ice and gas
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• Simple molecules and complex chemistry in a protoplanetary disk: A JWST investigation of the highly inclined disk d216-0939
• Peptide Bonds in the Interstellar Medium: Facile Autocatalytic Formation from Nitriles on Water-Ice Grains
• Millimetre and submillimetre spectroscopy of isobutene and its detection in the molecular cloud G+0.693
• Planet formation in chemically diverse and evolving discs -- I. Composition of planetary building blocks
• Molecules in the peculiar age-defying source IRAS 19312+1950
• Charting Circumstellar Chemistry of Carbon-rich AGB Stars: I. ALMA 3 mm spectral surveys
• Evolution of Fullerenes in Circumstellar Envelopes by Carbon Condensation: Insights from Reactive Molecular Dynamics Simulations
• Assessing realistic binding energies of some essential interstellar radicals with amorphous solid water. A fully quantum chemical approach
• CoCCoA: Complex Chemistry in hot Cores with ALMA. The chemical evolution of acetone from ice to gas
• Photochemistry of interstellar ice forming Complex Organic Molecules
• The SPHEREx Target List of Ice Sources (SPLICES)
• Design and Implementation of a New Apparatus for Astrochemistry: Kinetic Measurements of the CH + OCS Reaction and Frequency Comb Spectroscopy in a Cold Uniform Supersonic Flow
• King-plot analysis of isotope shifts in simple diatomic molecules
• H2CN/H2NC abundance ratio: a new potential temperature tracer for the interstellar medium
• A Low Temperature Kinetic Study of the C(3P) + CH3OCH3 Reaction. Rate constants, H-atom Product Yields and Astrochemical Implications
• A deep search for Complex Organic Molecules toward the protoplanetary disk of V883 Ori
• Axions in Andromeda: Searching for Minicluster -- Neutron Star Encounters with the Green Bank Telescope
• A rich molecular chemistry in the gas of the IC 348 star cluster of the Perseus Molecular Cloud
• Infrared Spectroscopy of Pentagon-Containing PAHs: Indenyl and Fluorenyl Anions and Indenyl Cation
• Millimeter wave spectrum and search for vinyl isocyanate toward Sgr B2(N) with ALMA
• A comprehensive rotational study of astronomical iso-pentane within 84 to 111 GHz
• Protostars at Subsolar Metallicity: First Detection of Large Solid-state Complex Organic Molecules in the Large Magellanic Cloud
• Density Functional Theory Calculations on the Interstellar Formation of Biomolecules
• Searching for Propionamide (C2H5CONH2) Toward Sagittarius B2 at Centimeter Wavelengths
• PRODIGE VI -- Envelope to Disk with NOEMA: VI. The Missing Sulfur Problem
• Millimetre-wave spectroscopy of 2-hydroxyprop-2-enal and an astronomical search with ALMA
• A detection of sulfur-bearing cyclic hydrocarbons in space
• A deep Search for Ethylene Glycol and Glycolonitrile in the V883 Ori Protoplanetary Disk
• Rotational Excitation of Vinyl Cyanide by Collisions with Helium Atoms at Low Temperature
• A 3 mm Molecular Line Survey toward The C-star Envelope CIT 6
• Correlations among complex organic molecules around protostars: Effects of physical structure
• New SiS destruction and formation routes via neutral-neutral reactions and their fundamental role in interstellar clouds at low and high metallicity values
• Linking ice and gas in the Coronet cluster in Corona Australis
• Extensive ro-vibrational analysis of deuterated-cyanoacetylene (DC${}_3$N) from millimeter-wavelengths to the infrared domain
• Photocleavage of aliphatic C--C bonds in the interstellar medium
• Water emission tracing active star formation from the Milky Way to high-$z$ galaxies
• FAST Observations of Four Comets to Search for the Molecular Line Emissions between 1.0 and 1.5 GHz Frequencies
• Coding Cross Sections of an Electron Charge Transfer Process
• Mutual neutralization of C${}_{60}^{+}$ and C${}_{60}^{-}$ ions: Excitation energies and state-selective rate coefficients
• The SKA as a prebiotic molecule detector
• Toward Unraveling Cyanopolyyne Surface Chemistry: A Preview on Isolated Systems From HC_{3}N to Ethyl Cyanide and Propylamine
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• An 18-25 GHz spectroscopic survey of dense cores in the Chamaeleon I molecular cloud
• Long-Range Complex in the HC3N + CN Potential Energy Surface: Ab Initio Calculations and Intermolecular Potential
• The LMT 2 millimeter receiver system (B4R). II. Science demonstration observations toward Orion-KL/OMC-1
• Kinetic Study of the Reactions of Ground State Atomic Carbon and Oxygen with Nitrogen Dioxide over the 50-296 K Temperature Range
• Formation of hydroxy, cyano and ethynyl derivatives of C4H4 isomers in the interstellar medium
• Collisional Excitation in Space: Recent Advances and Future Challenges in the JWST Era
• Charting circumstellar chemistry of carbon-rich asymptotic giant branch stars. II. Abundances and spatial distributions of CS
• Methyl Isocyanate Formation from Oxygen Insertion in Methyl Cyanide Ices
• Deep survey of millimeter RRLs towards the planetary nebulae IC 418 and NGC 7027
• Stability of C${}_{59}$ Knockout Fragments from Femtoseconds to Infinity
• TeraHertz Desorption Emission Spectroscopy (THz DES) of space relevant ices
• Pulsed ion deflection to overcome detector saturation in cryogenic ice sampling
• Hydroxylamine in Astrophysical Ices: IR Spectra and Cosmic Ray-Induced Radiolytic Chemistry
• Hunting for methanol in the water rich, planet forming disk around HL Tau
• Research on the Interstellar Medium and Star Formation in the Galaxy: An Indian Perspective
• A meta-analysis of molecular spectroscopy databases, and prospects of molecule detection with some future facilities
• Protoplanetary Disk Chemistry
• Chemistry of Dark Molecular Clouds
• Automated Exploration of Radical-Molecule Chemistry: The Case of Oxirane + CH in the ISM