![Chemical abundance distributions of the Sample II planet-candidate host stars in the [Fe/H]–[Mg/Fe] plane.](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/A-chemo.png?resize=1200%2C715&ssl=1)
[astro-ph.SR] To date, all known exoplanetary systems have been identified around stars currently residing in the Milky Way, whereas planets formed in external galaxies remain largely unexplored. Such systems would […]
astro-ph.SR
![The top panel shows comparisons of the observed spectrum of JADES-GS-BD-11 (black with grey 1σ error bars) and the median retrieved spectrum for both the PH3 and non-PH3 petitRADTRANS (red and green, respectively, with 1σ central credible intervals shaded around the median). The bottom panel shows the difference between the retrieved and observed spectra, divided by the observed uncertainty. The two retrieved median spectra are generally within 1σ of each other everywhere except at 4.3 µm (the Q-branch of the PH3 feature).-- [astro-ph.SR]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/JWSTNIRSpec.png?resize=1200%2C717&ssl=1)
Posted inBrown Dwarfs
JWST/NIRSpec Spectra for Three Ultracool Brown Dwarfs Detected in Extragalactic Surveys: Further Evidence for Phosphine Absorption
[astro-ph.SR] We present JWST NIRSpec prism spectra for three ultracool brown dwarfs discovered in extragalactic survey data, two from the JWST Advanced Deep Extragalactic Survey (JADES), and one from Public […]
Posted inSpace Weather & Heliophysics
Intense but Harmless: Exo-Space Weather Around an M Dwarf with a Single-Hemisphere Dynamo
[astro-ph.SR] M dwarfs are among the most promising host stars in the search for habitable exoplanets. However, their active atmospheres drive intense magnetic activity, including energetic flares and possibly coronal […]
![TiO absorption variation during 8 years on surface of proxima centauri. Vertical lines depicts regions were used to measure B index. -- [astro-ph.SR]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Titanium-Oxide.png?resize=1200%2C715&ssl=1)
Posted inProxima Centauri
Titanium Oxide Absorption as a Proxy to Detect Long term Variation and Activity Cycle in Proxima Centauri
[astro-ph.SR] Stellar activity cycles on magnetically active stars can be estimated by molecular absorption bands.
![Chemical structure of the aromatic nitriles cyanobenzene, d5-cyanobenzene, 1,2-dicyanobenzene, 1,3- dicyanobenzene and 1,4-dicyanobenzene -- [astro-ph.SR]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Infrared.png?resize=1200%2C714&ssl=1)
Posted inAstrochemistry
Infrared Spectroscopy and Photochemistry of Aromatic Nitriles in Para-Hydrogen Matrices
[astro-ph.SR] Motivated by recent detections of several aromatic nitriles in Taurus Molecular Cloud-1, we report laboratory and theoretical investigations of the vibrational spectroscopy and photochemistry of singly and doubly cyano-substituted […]
Posted inAstrochemistry
An Interstellar Energetic And Non-aqueous Pathway To Peptide Formation
[astro-ph.SR] The origin of the molecular building blocks of life is a central question in science. A few α-amino acids such as glycine, the simplest proteinogenic amino acid, have been […]
![Multiwavelength images of the two > 4𝜎 SJH candidates. Top: KIC 6606183. Bottom: KIC 9834255. Columns: WISE W1–W4 and Aladin DSS colour composite. Nearby sources are visible but their physical association requires high-resolution imaging. -- [astro-ph.SR]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/Stellar-J.png?resize=1200%2C720&ssl=1)
Posted inSETI & Technosignatures
Stellar J-Harvesting: A Novel Angular Momentum Technosignature And First Search In The Kepler Field
[astro-ph.SR] We introduce Stellar J-Harvesting (SJH), a technosignature in which an engineered system extracts rotational angular momentum from a star.
![The Rapid ASKAP Continuum Survey (RACS) radio images of radio sources associated with candidates A (J1245-2652, top row) and B (J0356-4031, bottom row) are shown at three frequencies: 887.5 MHz (left), 1367.5 MHz (centre), and 1655.5 MHz (right), with each panel covering a field of view of 65" × 65" . White ellipses show the PyBDSF source fits from the RACS catalogues, with thick solid lines indicating the fits at the frequency of the image, while thin dashed lines show fits from the other radio frequencies for comparison. Large blue crosses (×) mark radio source positions for the corresponding frequency, and small blue plus signs (+) indicate positions at other frequencies. The red stars represent the Gaia positions propagated to the corresponding RACS observation epochs using the measured proper motions. -- [astro-ph.SR]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/Archival-Diagnostics.png?resize=1200%2C720&ssl=1)
Posted inSETI & Technosignatures
Archival Diagnostics for Potential Background Contaminants Of Project Hephaistos Dyson Sphere Candidates
[astro-ph.SR] We report on the diagnostic inspection of nine Project Hephaistos Dyson Sphere candidate M-dwarfs based on archival data. By comparing the Gaia positions, propagated to the AllWISE epoch, with […]
![The figure illustrates the four main phases of low-mass star formation: from the gravitational collapse of the natal core of gas and dust (Prestellar Core), to the main accretion phase (Class 0/I protostar, age ∼104 -105 yr), followed by the protostar and its surrounding protoplanetary disk (Class I/II, age ∼105 -106 yr), and finally the revealed planetary system after the disk has dispersed (Class III, age ∼107 yr). Typical spatial and timescales are indicated for each stage. Generated with Google Gemini 3 Flash and modified. -- [astro-ph.SR]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/07/Cradle-of-Life.png?resize=1200%2C714&ssl=1)
Posted inHabitable Zones
Cradle Of Life: From The Formation Of Stars To Habitable Worlds With The SKAO
[astro-ph.SR] This chapter provides an overview of the different science cases covered by the “Cradle of Life” working group, which aims to leverage the capabilities of the Square Kilometre Array […]
Posted inAstrochemistry
Astrochemical Study of Early Embedded Discs
[astro-ph.SR] The question of how our planet was formed and, more generally, how a planetary system forms is fundamental and has been addressed in a broad range of research domains. […]