astrochemistry Archives

Sticking coefficients for selected elements onto amorphous carbon as a function of gas temperature Tg and dust temperature TD.

Efficient Interstellar Grain Growth From High Sticking Coefficients On Amorphous Carbon Dust

by Keith CowingJuly 20, 2026July 20, 2026

[astro-ph.GA] Cosmic dust is the solid phase of the interstellar medium (ISM), classically assumed to be composed of carbonaceous and silicate grains with size distributions spanning ∼5 Å to ∼1 […]

Residue of the Cretaceous-Paleogene impact. Dark clay-rich KT boundary layer in Stevn’s Klint, Denmark used in the study. Credit: Dr. Philippe Claeys.

Impact events

Researchers Identify Class Of Oddball Meteorite That Killed Earth’s Dinosaurs

by Keith CowingJuly 20, 2026July 20, 2026

[University of British Columbia] A rare CO chondrite meteorite was the probable impactor that struck Earth 66 million years ago, wiping out 75 per cent of Earth’s species, including non-avian […]

C1 clasts in Hillsborough: On the left is a back-scattered electron image with two C1 748 clasts circled. On the right, an X-ray map of the same area as (A), indicating Na enrichment in 749 of the C1 clasts relative to the bulk of Hillsborough. Credit: NASA/SETI

Meteorites & Asteroids

Pristine Meteorite Examination Adds To Our Knowledge Of Ancient Asteroids

by Keith CowingJuly 19, 2026July 19, 2026

[NASA] A meteorite recovered immediately upon its fall to Earth on July 16, 2024, is helping NASA scientists uncover new clues about ancient water, the chemical evolution of primitive asteroids, […]

This artist’s concept depicts a near-Earth asteroid with an elongated orbit. A few objects such as these can exhibit significant perturbations in their motion around the Sun and, like the asteroid 1998 SH2, could turn out to be regular comets with a weak tail and coma (the gas and dust around a comet’s nucleus). Credit: NASA/JPL-Caltech

Comets and Asteroids

NASA Study Finds Near-Earth Asteroid Is Actually Comet

by Keith CowingJuly 19, 2026July 19, 2026

[NASA] The object looks like an asteroid but moves like a comet, so astronomers used some of the most powerful observatories on the planet to confirm its identity.

Planet growth and migration tracks for the formation of WASP-19 b starting from different initial orbital locations. Solid parts of the tracks indicate the pebble-accretion phase before the planet reached pebble isolation mass, while dotted parts indicate the subsequent gas-accretion phase. Different symbols indicate different disc viscosities (α = 10−3 , 5 × 10−4 , and 10−4 ). The colour of each track represents the resulting atmospheric C/O ratio of the planet. -- [astro-ph.EP]

Exoplanets, -moons, -comets

The Majority Of Hot Jupiters Formed Beyond The Water Ice Line

by Keith CowingJuly 18, 2026July 18, 2026

[astro-ph.EP] Atmospheric compositions of giant exoplanets can retain information about their formation environments, as volatile species condense at different temperatures in protoplanetary discs.

Icy Worlds

Tracing The Source Of Carbon Oxides On The Large Moons Of Uranus

by Keith CowingJuly 18, 2026July 18, 2026

[astro-ph.EP] The Uranian moons Ariel, Umbriel, Titania, and Oberon are enriched in CO2 mixed with CO, but the origin(s) of these carbon oxides, be they primarily native or radiolytic, remains […]

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

Astrochemistry

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 […]

Time evolution of the probability distribution of the system for different temperatures as labeled and for fixed parameters: V=106 km3 , L=10 53 erg/s, r=0.01 AU, Grac=26.30 kJ/mol. The vertical axis is enantiomeric excess, and the horizontal axis is time in Myr scale. -- [astro-ph.HE]

Astrochemistry

Supernova Neutrinos And The Origin of Biomolecular Homochirality

by Keith CowingJuly 16, 2026July 16, 2026

[astro-ph.HE] We investigate the role of parity-violating interactions between supernova neutrinos and chiral molecules in nearby interstellar molecular clouds as a potential source of biomolecular homochirality.

The New jersey meteorite -- [SETI Institute]

Astrochemistry

Alien World Chemistry Found Inside A Meteorite that Struck A New Jersey Home

by Keith CowingJuly 15, 2026July 15, 2026

[SETI Institute] On July 16, 2024 a daytime meteor shook New York City with a sonic boom as it passed just south of the Statue of Liberty. Now, an international […]

[Top] Spin density plot of H2S on a charged surface. The red lobe visualizes where the extra electron resides within the complex. In both (a) and (b), the extra electron is located in a pocket created by the coordination of nearby H-atoms from both the ASW surface and the H2S molecule. [BOTTOM] SO2 on a (a) neutral surface and on a (b) charged surface. Panel (a) shows both the S - - O interaction and the dH - - O interaction often found in these neutral ASW/SO2 complexes. The wireframe in panel (b) shows the spin density of the charged ASW/SO2 complex. The extra electron clearly resides in the LUMO of SO2 and interacts with the surface through multiple dH - - O interactions. -- [astro-ph.GA]

Astrochemistry

Effect Of Ice Charging On The Astrochemistry Of Interstellar Sulfur Bearing Species On Amorphous Solid Water

by Keith CowingJuly 14, 2026July 14, 2026

[astro-ph.GA] We aim to derive statistically robust and physically interpretable BE distributions for atomic S and the sulfur-bearing molecules H2S, SO2, and OCS on neutral and negatively charged ASW, and […]