![Images acquired on 2019 October 4 (left) and 27 (right) with LDT. The top row show stacks of r and CN images, respectively. The bottom row shows the same images enhanced by subtraction of an azimuthal median profile. The enhanced CN images have been smoothed with a Gaussian profile to better reveal the faint underlying structure. A compass indicating north (N), east (E), the anti-sunward direction (−⊙), and the anti-velocity vector (−v) are overlaid on the r panels, while a scale bar showing a distance at the comet of 20,000 km is given on the CN panels (1 arcsec corresponds to 2134 km on October 4 and 1814 km on October 27). All four panels for a given night have the same orientation and physical scale at the comet. The October 4 image is a single frame and shows several artifacts that could not be removed without a median combination include several bright pixels in the CN frame (yellow) and a bad column in all frames (black diagonal line). On October 4, a bright star is seen near the left edge of the r frames and as a diagonal (yellow) line in the upper right in CN. Two faint trailed stars are visible in the r images on October 27. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/The-Highly.png?resize=1200%2C720&ssl=1)
[astro-ph.EP]. We report on imaging, spectroscopy, and narrowband photometry of interstellar comet 2I/Borisov obtained at Lowell Observatory from 2019 September 13 to December 16.
Comets and Asteroids
![Occam’s razor-based deconvolution result of the subset of signals associated with CnHmN parent and fragment species detected by the DFMS on 3 August 2015. The measured signals (measured) are given in arbitrary units (a. u.) with 30 % error margins. The different contributions of the chosen candidate molecules are colour-coded according to their molecular structure – in shades of red and purple for chain-based molecules and in shades of green and blue for cyclic molecules. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Nitrogen.png?resize=1200%2C707&ssl=1)
Posted inComets and Asteroids
Nitrogen- And Nitrogen-oxygen-bearing Organic Molecules In Comet 67P/Churyumov-Gerasimenko: An Untargeted Investigation
[astro-ph.EP] Comets provide a unique window into the history of the Solar System as they carry some of the best-preserved material and make it available to in situ exploration.
Posted inTricorders & Sensors
New UC Riverside Lab Focuses on Cutting Edge Astrobiology Tools
[UC Riverside] The Planetary Geochemistry and Astrobiology Laboratory is led by Assistant Professor Fabian Klenner, a new faculty member in UCR’s Department of Earth and Planetary Sciences. His research focuses […]
![Upper Panels. Maps of N × ρ for ortho-H2O and para-H2O, the derived OPR, and Trot(H2O) for the 6 µm band measured on February 28. Note that N for each species has been corrected for the derived OPR. Lower Panels. As in the upper panels for the 2.6 µm H2O bands measured on March 1. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/JWST-Spatial.png?resize=1200%2C727&ssl=1)
Posted inComets and Asteroids
JWST Spatial-Spectral Mapping of Green Comet C/2022 E3 (ZTF)
[astro-ph.EP] We report a survey of molecular emission from cometary volatiles using the James Webb Space Telescope (JWST) toward Oort cloud comet C/2022 E3 (ZTF) carried out on UT 2023 […]
![Example of the stacking procedure for the Maidanak data obtained on 2025 August 15, based on ten 60 s exposures in each of the B, V , and R filters. Left: Comet-centered stack, showing the coma morphology without trailing of the comet signal. The pink circle indicates an aperture radius of 10 000 km. Right: Sidereal stack used for photometric calibration, in which the comet appears trailed.-- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/The-Inbound.png?resize=1200%2C720&ssl=1)
Posted inComets and Asteroids
The Inbound Gas and Dust Evolution of Interstellar Comet 3I/ATLAS from Optical Spectroscopy and Multi-band Photometry
[astro-ph.EP] Interstellar objects (ISOs) provide direct constraints on the composition and evolution of extrasolar planetary systems. As the third confirmed ISO, comet 3I/ATLAS offers a rare opportunity to study pristine […]
Posted inComets and Asteroids
An Enriched Methane D/H Ratio in the Interstellar Object 3I/ATLAS
[astro-ph.EP]. Interstellar objects are interlopers from other planetary systems, and their volatile compositions provide a glimpse into planet formation around their host star.
Posted inPhobos
Infrared-to-visible Albedo Ratio Of Phobos: Comparison With Primitive Asteroids
[astro-ph.EP] Aims. The ratio between infrared and visible albedo, pIR/pV, provides a simple proxy for the spectral slope of asteroid surfaces between the visible and near-infrared wavelength ranges. The aim […]
![Ni, Cu and Zn elemental maps of three chondrules from Paris, that show microspherule regions partitioned by zones enriched in siderophile elements (i.e., Fe, Ni, Co, Cu; pink arrows). The color bars reflect μg/g concentrations of the elements. While in BSE mode and lithophile element space, these would appear as single ~300 μm diameter chondrules, they represent aggregates of ~100 μm grape-bunch chondrules (pink spheres), where these microchondrules contained metal-rich rims. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Chondrule.png?resize=1200%2C714&ssl=1)
Posted inAstrogeology
Chondrule Formation In The Outer Disk From The Primary Three-dimensional Chemical Composition Of CM Chondrules
[astro-ph.EP] Chondrules and their associated fine-grained rims record key processes in the early protoplanetary disk, yet the links between chondrule chemistry, morphology, and matrix complementarity remain poorly constrained.
Posted inAstrogeology
Setting The Stage: The Early History Of The Solar System
[astro-ph.EP] This article reviews the early history of our solar system from an astrobiological perspective and presents evidence from meteorites and astronomical observations. The purpose is to trace the formation […]
![Inclination vs. semimajor axis for the NEOs. The main asteroid families that have been linked to ordinary chondrites are represented by gray squares. The ν6 secular resonance with Saturn and the 3:1 and 5:2 mean motion resonances with Jupiter are represented with dashed lines. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Size-Constraints.png?resize=1200%2C718&ssl=1)
Posted inAstrogeology
Size Constraints For The Pre-atmospheric Parent Bodies Of Ordinary Chondrites
[astro-ph.EP] The study of S-complex near-Earth objects (NEOs), the parent bodies of ordinary chondrites, has shown that they are dominated by asteroids with LL chondrite-like compositions. This is surprising because […]