![(A) C1 clast containing numerous magnetite (white), pyrrhotite (light gray), and dolomite grains (dark gray). (B) C1 clast with numerous dolomites marked “D,” indicating the dolomite crystal where the FIB was cut (bottom, arrowed, and outlined in yellow). (C) Bright-field TEM image of the FIBed dolomite crystal. Numerous cracks are arrowed. (D) Na x-ray map of the same area as in (C). -- [Science Advances]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/Meteor-over-New-.png?resize=1200%2C715&ssl=1)
[Science Advances] The CI (Ivuna-type) carbonaceous material returned from asteroids Ryugu and Bennu contain mobilized sodium from the evaporation or freezing of liquid water into brines, shedding light on the […]
Biochemistry & Organic Chemistry
![Schematic diagram (not to scale) of the experimental apparatus used for benzene ice nucleation and growth studies (adapted from Dubois et al. (2021)). Pressure was measured with a capacitance manometer (P1) and an ion gauge (P2). The inset shows a top view of the cooled sample holder with the positions of the three K-type thermocouple gauges (red dots) used for temperature measurements. The ice sample formed on either or both sides of the silicon substrate/tholin sample (grey), which was in the path of the IR beam of the Thermo Fisher iS50. Infrared transmission spectra were collected with a liquid N2-cooled MCT/A detector. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/Experimental-Measurements.png?resize=1200%2C717&ssl=1)
Posted inTitan
Experimental Measurements of Benzene Ice Critical Saturation Ratios on Titan Tholins and Impact on the Microphysical Modeling of Titan’s South Polar Benzene Cloud
[astro-ph.EP] The Cassini Composite Infrared Spectrometer (CIRS) revealed the presence of a benzene (C6H6) ice cloud in Titan’s autumn south polar stratosphere, following the northern spring equinox in August 2009.
Posted inComets and Asteroids
A Comprehensive Study Of Comet 67P/Churyumov-Gerasimenko In The 2021/2022 Apparition. II. Colorimetry, Polarimetry, Modeling
[astro-ph.EP] This paper presents the second part of our multi-technique observational study of comet 67P during its 2021-2022 apparition. While the first paper focused on photometry and spectroscopy, here we […]
![DFT-computed anharmonic absorption spectra of 1-cyanonaphthalene in its neutral (1-CNN0 , top panel), cation (1-CNN+ , middle panel), and anion (1-CNN− , bottom panel) charge states. The calculated vibrational transitions are convolved with a Lorentzian profile using a FWHM of 4 cm−1 to simulate realistic spectral profiles. Numerical labels near the major peaks represent their respective wavelengths. Key vibrational bands, including the CN stretch at ∼ 4.4–4.6 µm and the CH stretch at ∼ 3.2–3.3 µm, are explicitly highlighted.-- [astro-ph.GA]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/Anharmonic-Infrared-Emission.png?resize=1200%2C718&ssl=1)
Posted inAstrochemistry
Anharmonic Infrared Emission Of Cyano-Substituted Polycyclic Aromatic Hydrocarbon Molecules: Cyanonaphthalenes As A Case Study
[astro-ph.GA] Recent detections of cyano-substituted polycyclic aromatic hydrocarbons (cyano-PAHs) highlight them as key tracers of nitrogen heterocycles in the interstellar medium (ISM).
![Recombination transferred part of archaeal YRS into non-canonical bacterial YRS. A) YRS core catalytic domain alignment from archaeal (indicated left as blue), bacterial non-canonical (purple) and bacterial canonical (pink) sequences. Both recombinant and nonrecombinant YRSs are found within all four major bacterial supergroups (Terrabacteria, Proteobacteria, PVC and FCB) B) Speciestree reconciled consensus trees reconstructed for the non-recombinant (left) and recombinant YRS sites (right). Branch lengths were estimated using NQ.bac+R10 in IQ-Tree v2.1.332. -- [biorxiv.org]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/Tryptophan-became.png?resize=1200%2C720&ssl=1)
Posted inOrigin & Evolution of Life
Tryptophan Became Part Of The Universal Genetic Code Post-LUCA
[biorxiv.org] We evaluate whether tryptophan (W), widely thought to be the last of the 20 canonical amino acids added to the genetic code, was already present in the Last Universal […]
Posted inComets and Asteroids
The Polana-Eulalia Complex with JWST NIRSpec: Connections to Bennu, Ryugu, and Outer Solar System Bodies
[astro-ph.EP] Carbon rich [C complex] asteroids provide insight into the early Solar System, and families of C complex asteroids serve as robust samples for learning about the internal structure of […]
![Gas-phase abundance evolution of CH3OH, CH3CHO, CH3OCHO, and CH3OCH3 in the representative warm-up model with Tmax = 200 K. The shaded rectangles indicate the observed abundance ranges derived in this work. The gray vertical band marks the time interval, (1.25–1.42) × 106 yr, over which the model abundances overlap most closely with the observed ranges for the four species. -- [astro-ph.GA]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/Molecule-dependent.png?resize=1200%2C720&ssl=1)
Posted inAstrochemistry
Molecule-dependent Abundance Behavior of Oxygen-bearing Complex Organics in High-Mass Star-Forming Regions: A Uniform 50-source Survey
[astro-ph.GA] We present a uniform IRAM-30m survey analysis of four oxygen-bearing complex organic molecules (COMs), methanol (CH3OH), acetaldehyde (CH3CHO), methyl formate (CH3OCHO), and dimethyl ether (CH3OCH3), toward 50 high-mass star-forming […]
Posted inAstrochemistry
ALMA Central Molecular Zone Exploration Survey (ACES) I: Overview
[astro-ph.GA] The mass flows and energy cycles within the inner regions of galaxies exert a powerful influence on the evolution of the galaxy population.
![a) Biological evolution as stochastic optimization: Initially, wild-type cells x grow up a population. A mutant y grows up a population. The populations x and y compete. The winner (greater population) then fetches more resources. Fitness landscapes at the bottom show how the mutant is an experiment, where the winner decides the next step direction. b) Evolution annotated in terms of the Central Dogma: (Left, green) Wildtype starting point, NA encodes PR, which gives fitness F. (Top, red), Mutation in the blueprint NA, becoming NA’. (Red, green) both NA sequences grow up into populations. (Next) The populations compete for fitness. The winner, Fx now carries with it the winning sequence NAx and protein P Rx. -- [biorxiv.org]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/RNA-And-Proteins.png?resize=1200%2C720&ssl=1)
Posted inOrigin & Evolution of Life
RNA And Proteins Joined Up At The Origins Of Life: Persistence Is The Point
[biorxiv.org] What drove nucleic acids (NA) to associate with proteins (PR) at the Origins of Life? We reason from polymer physics and the Central Dogma (CD) that the fitness value […]
![Most theoretical work on the origin of heredity has focused on how genetic information can be maintained without mutational degradation in the absence of error-proofing systems. -- [PLOS Biology]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/Selection-For.png?resize=1200%2C715&ssl=1)
Posted inGenomics, Proteomics, Bioinformatics
Selection For Growth Drives The Emergence Of Genetic Heredity In Protocells
[PLOS Biology] A simple and parsimonious solution assumes the first gene sequences evolved inside dividing protocells, which enables selection for functional sets. But this model of information maintenance does not […]