![Full JWST spectrum of HOPS-68. We indicate the molecular absorption bands of oxygen-bearing molecules as studied in this work (SiO, H2O, CO2 and CO) and of carbon-bearing molecules as studied in paper B, as well as the most notable ice and silicate absorption features. Not indicated are 13CCH2, CS, and CH4 in the 7.3-7.8 µm region, and CH3, C4H2 and C6H2 around ∼ 16 µm, which will all be studied in paper B. Some prominent H2 emission lines are highlighted with a black arrow. HOPS-68 is not detected in continuum at wavelengths lower than 2.2 µm. The inset shows a zoom-in to the 7.8-8.6 µm region, which highlights the detection of SiO. -- [astro-ph.SR]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/A-breath.png?resize=1200%2C558&ssl=1)
[astro-ph.SR] Recently, an analog to the t = 0 moment of our Solar System’s meteoritic record was identified for the first time around the Class I protostar HOPS-315.
astro-ph.SR
![Column density maps of 13CO2, CO and OCN− ice (panel I, II and III, respectively). 12CO2 column densities are derived from 13CO2 column densities. Panel IV shows the ratio between the 4.38 µm and 4.39 µm peak of the 13CO2 ice feature. A higher ratio indicates higher degree of CO2 ice segregation. The axes are shown on astronomical unit scales. Pixelated areas especially in the north and south of the maps as well as the edges are caused by low signal-to-noise levels. -- [astro-ph.SR]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/Mapping.png?resize=1200%2C718&ssl=1)
Posted inAstrochemistry
Mapping Of Interstellar Ices With JWST In Protostellar Envelopes: Spatial Variations Of 13CO2, 12CO2, CO, OCN− and H2O ice
[astro-ph.SR] The composition of planets and their atmospheres is largely determined by the formation environment of the planet. This environment is pre-determined during early stages when the protostar is still […]
![Absolute CSs for the reaction of P+ with C2H2, measured at ECM = 0.14 eV as a function of the photon energy. Products are detected at m/z 56 (HCCP+, orange triangles) and m/z 55 (CCP+, blue circles). From Ephot ≈23 eV an additional product is observed at m/z 26 (C2H2 +, black squares). The vertical dashed black line indicates Ephot value at which CS trends as a function of ECM have been measured. Grey and red arrows indicate the calculated thermodynamic thresholds for production of P+ in ground and excited states, as detailed in the text.-- [astro-ph.SR]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/Synthesis.png?resize=1200%2C717&ssl=1)
Posted inAstrochemistry
Synthesis Of Organo-phosphorous Species In Space: The Reaction Of P+ With C2H2
[astro-ph.SR] Despite its low cosmic abundance, phosphorus is a bioessential element whose prebiotic availability and incorporation into biomolecules remain open questions. Only a few phosphorous containing molecules with P to […]
![Sky map of the Plato benchmark stars in Galactic coordinates. Different symbols indicate benchmark quality samples as defined in the text (Sect. 5.3). Symbol size increases with apparent brightness. -- [astro-ph.SR]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/10/Plato-benchmark.png?resize=1200%2C719&ssl=1)
Posted inPLATO
Plato Benchmark Stars I. The Initial Benchmark Sample I
[astro-ph.SR] The ESA PLATO mission aims to detect and characterise Earth-size exoplanets orbiting bright, late-type stars using high-precision photometry and asteroseismology.
![Wavelength distributions of candidate spectral lines retained at each step of the line-selection procedure. The histograms show the initial linelist (light), lines retained after automated vetting (intermediate), and the final manually vetted sample (dark). The shaded background regions indicate approximate wavelength ranges for the Y, J, H, and K-bands.-- [astro-ph.SR]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/09/Elemental.png?resize=1200%2C716&ssl=1)
Posted inStellar Cartography
Elemental Abundances of Cool Stars: A Spectroscopic Framework Applied to Five Planet-Host Stars
[astro-ph.SR] Stellar elemental abundances provide important constraints on the chemical environments from which planets form. M and late-K dwarfs are prime targets for the characterization of small exoplanets, yet their […]
![Panel (a): HR diagram of the OC members with detections. The blue solid line is the fitting results of MS. green dashed lines represent the upper and lower bounds of the MS fitted with a ±0.5 offset, and the red dashed line is the same sequence shifted upwards by 2. The color bars represent the stellar ages. Panel (b): HR diagram of the field stars with detections. Panel (c): The Galactic distribution of the selected sources from the detected OC members. Panel (d): The Galactic distribution of the selected sources from the detected field stars. -- [astro-ph.SR]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/09/Evolution-of.png?resize=1200%2C720&ssl=1)
Posted inHabitable Zones
Evolution of Stellar Activity and Habitable Zone (EATEN): III. X-ray Activity of Dwarfs in Open Clusters and Field Stars
[astro-ph.SR] Stellar X-ray emission serves as a direct diagnostic of coronal activity, which is fundamentally linked to coronal heating processes. It also strongly influences the atmospheres and long-term habitability of […]
![Cumulative oxygen loss for planets at the habitable zone of each sample star over 1 Gyr, assuming constant stellar XUV flux at the HZ and no replenishment of oxygen. The curves are calculated using the energy-limited O2 loss prescription from V. S. Airapetian et al. 2017. Colored lines show individual stars, with solid segments representing the earliest ages (for stars with age ranges) and dashed segments extending beyond the minimum age. The black solid line shows the solar reference. Horizontal lines indicate the present-day Earth atmospheric O2 content (∼0.2 bars; dotted) and the total mass of Earth’s oceans (∼240 bars; dashed), providing reference levels for planetary habitability. -- [astro-ph.SR]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Panchromatic.png?resize=1200%2C720&ssl=1)
Posted inHabitable Zones
Panchromatic Spectra of Nearby Low-mass and Sun-like Stars with Directly Imageable Habitable Zones
[astro-ph.SR] Characterizing the high-energy radiation environments of stars plays a critical role in determining which systems’ planets are capable of retaining atmospheres and sustaining habitable conditions.
![Keck/NIRSPEC M -band spectrum of TRAPPIST-1 (black) with best-fit model (red). Top: echelle order 16 (λ ≈ 4.63–4.73 µm). Bottom: order 15 (λ ≈ 4.93–5.04 µm). Residuals (data minus model) are shown beneath each panel. Gray shading indicates the relative telluric transmission (dimensionless, 0–1). Masked pixels are omitted from the retrieval. -- [astro-ph.SR]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/The-Isotopic.png?resize=1200%2C721&ssl=1)
Posted inTRAPPIST-1
The Isotopic And Elemental Abundances of Planet-Host Star TRAPPIST-1
[astro-ph.SR]. Elemental and isotopic abundances are key tracers of planet formation, stellar evolution, and Galactic chemical evolution. Very low-mass stars are particularly interesting in this regard, because unlike more massive […]
![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)
Posted inStellar Cartography
A Chemo-dynamical Search For Planet-candidate Hosts Of Possible Extragalactic Origin
[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 […]
![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 […]