dust grain Archives - Astrobiology

This image by NASA’s James Webb Space Telescope’s Near-Infrared Camera (NIRCam) features the central region of the Chamaeleon I dark molecular cloud, which resides 630 light years away. The cold, wispy cloud material (blue, center) is illuminated in the infrared by the glow of the young, outflowing protostar Ced 110 IRS 4 (orange, upper left). The light from numerous background stars, seen as orange dots behind the cloud, can be used to detect ices in the cloud, which absorb the starlight passing through them. -- NASA larger image

Experimental Astrochemistry And Machine Learning Unravel The Formation Of Oxygen-bearing Organic Molecules In Extraterrestrial Ices

by Keith CowingJuly 16, 2026July 16, 2026

[Nature Communications Chemistry] Oxygen-bearing organic molecules, including aldehydes, alcohols, and peroxides, serve as key precursors to complex organics in extraterrestrial environments. Their non-equilibrium formation mechanisms critically constrain the molecular complexity […]

Optimised Fe0@SiO2 + C2H2 geometry of the molecular cluster used for the benchmark study. Colour coding: beige, Si atoms; red, O atoms; orange, Fe atoms; white, H atoms; grey, C atoms -- MRAS

Benzene Formation On Interstellar Dust Grain Analogues Via Single-Atom Fe Catalysis

by Keith CowingJuly 10, 2026July 10, 2026

[MRAS] Benzene has been detected across a range of astrophysical environments, though the primary mechanism underpinning its formation has not yet been constrained and the extreme conditions of the interstellar […]

Images of the total intensity of scattered light from debris disks detected with IRDIS, IFS, or ZIMPOL. The white bar at the bottom of each image corresponds to 1″. In all images, sky north is up and east is to the left. Original image -- Astronomy and Astrophysics

Astrochemistry, Astrogeology, Astronomy & Telescopes, Comets and Asteroids, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Press Release

SPHERE’s Debris Disk Gallery: Tell-tale Signs Of Dust And Small Bodies In Distant Solar Systems

by Keith CowingDecember 10, 2025December 10, 2025

Observations with the instrument SPHERE at ESO’s Very Large Telescope have produced an unprecedented gallery of “debris disks” in exoplanetary systems. Gaël Chauvin (Max Planck Institute for Astronomy), project scientist […]

(a) “Small” grain core assembled up of 1000 carbon atoms; (b) cross-section of a “small” grain core; (c) ’large’ grain core assembled up of 10000 carbon atoms; (d) cross-section of a “large” grain core. -- astro-ph.GA

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Imaging & Spectroscopy, Interstellar, Status Report

Off-lattice Microscopic Monte Carlo Modeling of Molecular Hydrogen Formation on Carbonaceous Dust Grains

by Keith CowingSeptember 11, 2025September 11, 2025

In this work, we present an off-lattice Monte Carlo model of accretion and migration of hydrogen atoms on a rough surface of carbon dust grain.

Performance of our neural networks after the training with the first training+validation split, with respect to the spectra included in the validation subset. The plots show the predicted versus true labeled values for the molecular fractions and temperature. Left panels: Molecular fractions of ice spectra. Each ice spectrum in the validation subset (with a certain composition and temperature) corresponds to six circles in the plot: one for each targeted molecule (denoted by colours). The sizes of the circles indicate the temperature of the ice. The bottom panel reports the difference between the predicted molecular fraction and the labeled value from the experiment. Right panels: Temperature of ice spectra, represented by each circle. Again, the bottom panel reports the difference between the predicted and the labeled values.-- astro-ph.IM

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

A Fast Machine Learning Tool To Predict The Composition Of Astronomical Ices From Infrared Absorption Spectra

by Keith CowingSeptember 5, 2025September 5, 2025

Current observations taken by James Webb Space Telescope (JWST) allow us to observe the absorption features of icy mantles that cover interstellar dust grains, which are mainly composed of H2O, […]

Images of dust continuum emission of the HL Tau disk. An arcsinh stretch is applied to the color scale. -- astro-ph.EP

Astrochemistry, Astrogeology, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Interstellar, Press Release

Multi-Wavelength Dust Characterization of the HL Tau Disk and Implications for Planet Formation

by Keith CowingJuly 25, 2025July 25, 2025

We present a comprehensive analysis of the HL Tau dust disk by modeling its intensity profiles across six wavelengths (0.45 to 7.9 mm) with a resolution of 0.05 arcsec (∼7 […]

The major COMs formation routes on grain surface. The COMs studied in our simulations have teal background. The species involved in the methanol formation chain are highlighted in bold. The chemical desorption in the COMs surface formation reactions is the main source of the gaseous COMs. The expressions +H and +H/−H2 together denote a pair of reactions, H-atom addition and H-atom abstraction. -- astro-ph.GA

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

Formation of Complex Organic Molecules in Prestellar Cores: The Role of Non-Diffusive Grain Chemistry

by Keith CowingJuly 6, 2025September 18, 2025

We present the results of astrochemical modeling of complex organic molecules (COMs) in the ice and gas of the prestellar core L1544 with the recently updated MONACO rate equations-based model.