astrochemistry Archives

Fractional abundances relative to H2 of the protonated Ca-bearing cyanopolyynes as a function of radius in Model A. -- astro-ph.SR

Astrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Imaging & Spectroscopy, Interstellar, Status Report

Ca-bearing Cyanopolyynes in IRC+10216

by Keith CowingJune 4, 2026June 10, 2026

In recent years, a number of metal-containing, carbon-chain species have been detected in the external circumstellar envelope of the carbon-rich AGB star IRC+10216.

Fig. 9: Distribution of water ice. The color map represents the smoothed Aice W1 values, where blue indicates the existence of water ice absorption. Several well-known regions are enclosed in boxes and labeled as regions 1 to 5, they are (1)Orion-Taurus-Perseus (OTP) region, (2)Cygnus Complex, (3)Serpens region, (4)Ophiuchus region and (5)Vela Co -- astro-ph.GA

Astrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Imaging & Spectroscopy, Interstellar, Status Report

The First Glimpse of Water Ice Absorption Map in the Milky Way

by Keith CowingJune 3, 2026June 3, 2026

Interstellar ice plays a key role in the thermal evolution of the interstellar medium and in astrochemical pathways, yet its large-scale distribution remains poorly constrained.

Time evolution of the fractional abundances of HCOOH, HC(O)SH, HC(S)SH, and CH3SH. Solid lines represent the fiducial model, including all grain-surface and gas-phase reactions. Dashed lines show the abundances obtained when grain-surface reactions 5 and 6 are switched off, adopting realistic rate coefficients for gas-phase reactions 1 and 2. Dotted lines correspond to models in which grain-surface reactions 5 and 6 are excluded and the upper limits of the rate coefficients for gas-phase reactions 1 and 2 are adopted. -- astro-ph.GA

Astrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Imaging & Spectroscopy, Interstellar, Status Report

Non-detection Of HC(S)SH: Estimating Upper Limits And Constraining Chemistry

by Keith CowingJune 3, 2026June 3, 2026

The search for dithioformic acid (t-HC(S)SH) in star-forming regions is crucial for understanding interstellar sulfur chemistry and addressing the ‘missing sulfur’ problem. Motivated by a recent claim of t-HC(S)SH detection […]

Astrobiology (general), Biosignatures & Paleobiology, Citizen Science / Open Science, Education and Outreach, Origin & Evolution of Life, Press Release

NWA Citizen Science Call 2026 (Astrobiology, Origin of life, Biosignatures)

by Keith CowingJune 2, 2026June 2, 2026

Dear all, We would like to draw your attention to the NWA Citizen Science Call 2026. This call offers citizen collectives the opportunity to investigate a societal question together with […]

Top: coma maps of H2O, CO2, and CH4, computed as the molecular column density from a pixel-by-pixel retrieval analysis for Observations 6, 15, and 6, respectively. The sunward and target velocity directions are denoted by the white arrows. The target centroids, computed as the photocenter in the median-stacked images (Figure 1), are marked with the black points. For H2O and CO2, the white contours correspond to emission levels of 50% and 20% relative to the maximum value and illustrate the slight antisunward extension of the respective comae. The contours are omitted in the CH4 panel, due to the poorer signal-to-noise ratio of the data. Bottom: corresponding median-stacked images across the continuum wavelengths within each fluorescence region. The H2O coma map shows a significant enhancement in the emission level at large nucleocentric distances relative to the dust continuum, indicating extended H2O production within the coma. -- The Astrophysical Journal Letters

Astrochemistry, Astronomy & Telescopes, Biogeochemical Cycles & Geobiology, Biophysics, Biosignatures & Paleobiology, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Interstellar, Press Release

Webb Detects Methane on Interstellar Comet 3I/ATLAS

by Keith CowingJune 2, 2026June 2, 2026

NASA’s James Webb Space Telescope has collected its first mid-infrared chemical fingerprint of an interstellar object during a recent revisit to comet 3I/ATLAS. The team’s results published recently in The […]

Abundances (w.r.t. H nuclei) of main C and O carriers in the baseline and full chemistry models without transport. C species represent the combination of all species containing carbon, but not oxygen; O species represent the species containing oxygen, but not carbon; C+O species represent the species containing both carbon and oxygen. From all the grouped species, the initially present H2O, CO2 , CO and CH4 are excluded. Solid lines represent ice-phase species, and dashed lines represent gas-phase species. -- astro-ph.EP

Astrochemistry, Astrogeology, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report

Metamorphoses Of Carbon And Oxygen In Protoplanetary Discs: How Chemistry And Radial Drift Transform Inner Disc C/O Ratios

by Keith CowingJune 2, 2026June 2, 2026

The chemical composition of a protoplanetary disc is sensitive to its thermal structure and dust properties, and can provide insights into the disc evolution.

A simplified illustration of the model. It depicts a cross-section of a spherical phospholipid vesicle, highlighting its membrane with hydrophilic heads and hydrophobic tails. Racemic d- and l-ribose (green) can both penetrate the membrane and capture the PO groups, but d-ribose undergoes this process more quickly and is preferentially trapped (purple) inside the vesicle. --Life

Astrochemistry, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Genomics, Proteomics, Bioinformatics, Status Report

Stereoselective Phosphorylation of d-Ribose as a Driver of Life’s Homochirality

by Keith CowingJune 1, 2026June 1, 2026

Life demonstrates remarkable homochirality of its major building blocks: nucleic acids, amino acids, sugars, and phospholipids. Phospholipid bilayer vesicles (liposomes) are formed at the water/air interface from Langmuir layers and […]

Integrated intensity maps of the dust continuum

Astrochemistry, Astrogeology, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report

The Asymmetric Carbon-rich Chemistry 0f The planet-forming Disk 0f HD 142527 Triggered By Late Infall

by Keith CowingJune 1, 2026June 1, 2026

The planet-forming disk of HD 142527 is known for its azimuthally asymmetric dust trap, shadows, and spiral arms.

Evolutions of fiducial planetesimals with different chondritic compositions. Each plot is the contour of one quantity across time and radial location. Note that the total radius decreases due to sintering. From top row to bottom: EH, OC, CV, and CI bodies. Physical quantities from left to right: (i) temperature, (ii) condensed + gaseous C abundance normalized to the initial reservoir; > 1 relative abundance occurs due to sintering concentrating C, (iii) porosity and (iv) gas pressure; hatched areas are completely sintered with no meaningful gas pressure. -- astro-ph.EP

Astrochemistry, Astrogeology, Meteorites & Asteroids, Status Report

Modeling Carbon Outgassing From Chondritic Planetesimals

by Keith CowingJune 1, 2026June 1, 2026

The thermochemical evolution of planetesimals is an underprobed stage of volatile delivery to terrestrial planets during their formation, and may contribute to the volatile depletion of the Earth relative to […]

Adsorption of crystals of a biological chiral molecule onto a gold-coated cobalt surface. Larger crystals of one specific form of the molecule (left) tend to accumulate on this surface to a greater degree than those of its mirror-image form (right). In the left image, the crystals reach heights of about 1.2 nm, whereas in the right image they do not exceed 0.8 nm. The physical advantage of one form over the other in accumulating on the magnetic surface suggests that, in a competitive setting, it would become the dominant (“winning”) form. -- Weizmann Institute of Science

Astrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Imaging & Spectroscopy, Interstellar, Press Release

A Glimpse At The Origins Of Life Through A Deceptive Mirror

by Keith CowingMay 29, 2026May 29, 2026

Imagine looking at yourself in the mirror, only to find that your reflection is governed by different laws than you are: Identical movements produce different outcomes, and what seems like […]