![Conceptual relation between cometary dust activity and the release of refractory organic material.-- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/11/Cometary-dust.png?resize=1200%2C716&ssl=1)
[astro-ph.EP] Cometary dust is an important reservoir of refractory organic matter and may contribute to the redistribution of carbon-rich material throughout planetary systems.
astro-ph.EP
![The habitable-zone correction at a glance. Each symbol is a TOI placed at a distance from the centre that scales with its insolation relative to the conservative habitable zone of its host (green ring; hotter planets inside, colder outside); symbol size scales with planet radius. Left: positions from the catalogue periods, which place 28 duo-transits in the conservative habitable zone. Right: positions from the periods of this work. Of the 28, nine are resolved and only two remain in the habitable zone, both giants (TOI-4600 c and TOI-1894.01); the 19 unresolved objects, drawn with opacity proportional to their probability of lying in the habitable zone, are expected to contribute 0.0–0.1. Two planets enter the habitable zone: TOI-6478 b, a duo-transit catalogued outside it, and TOI-2298 b, a mono-transit with no catalogue period. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/11/Are-habitable.png?resize=1200%2C720&ssl=1)
Posted inHabitable Zones
Are Habitable-zone TESS Objects of Interest really there? Period Resolution From The Full Archive
[astro-ph.EP]. TESS Objects of Interest (TOIs) seen as single or duo transits carry a catalogue period that is undefined or equal to the separation of the two events, and their […]
Posted inExoplanets, -moons, -comets
On The Detectability of Compact Multi-Planet Systems via Gravitational Microlensing
[astro-ph.EP] Compact multi-planet systems orbiting ultracool dwarfs, such as TRAPPIST-1, may be a major population of terrestrial worlds with poorly constrained demographics.
![Bolometric intensity map (right) from the M dwarf simulation of Table 1. The sketch on the left shows the approximate size of the numerical box with respect to the stellar radius, assuming a (R=0.4 R⊙ for a 3500K M dwarf star, Parsons et al. 2018). -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/11/The-impact.png?resize=1200%2C718&ssl=1)
Posted inExoplanets, -moons, -comets
The Impact of M Dwarf Stellar Convection on Exoplanetary Atmospheric Signatures. A 3D Radiation-hydrodynamics Simulation Analysis for High-resolution Spectroscopy
[astro-ph.EP] M dwarf stars represent prime targets for the detection and characterization of small, temperate exoplanets; however, their complex activity and convective surfaces pose significant challenges for high-resolution spectroscopic studies.
![Expected exocomet transit detection S/N as a function of central wavelength for 600 s integration, assuming an intrinstic dimming of 1 mmag for the 𝛽 Pictoris SED. The solid curve (𝑆 = 0) assumes a wavelengthindependent intrinsic dimming. The dashed curves (𝑆 = ±0.5) show illustrative wavelength-dependent signal scaling relative to the 𝑆 = 0 case. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/11/Signature.png?resize=1200%2C716&ssl=1)
Posted inExoplanets, -moons, -comets
Signature Of Exocomet Transits Observed With Ariel
[astro-ph.EP] We investigate the potential of the Ariel space telescope to detect and characterise exocomet transits through their wavelength-dependent photometric signatures.
Posted inExoplanets, -moons, -comets
Demographics of Close-In TESS Exoplanets Orbiting FGK Main-sequence Stars II. Spectral-Type Dependence and the Neptunian Landscape
[astro-ph.EP]. Understanding how planetary demographics depend on host star properties is essential for constraining planet formation and evolution theories.
![O2–O2 CIA impact on reflected-light spectra. Top: modern Earth composition (21 % O2). Bottom: otherwise identical O2-dominated composition (78 % O2), with N2 adjusted to keep total surface pressure fixed.[astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/11/Distinguishing.png?resize=1200%2C721&ssl=1)
Posted inExoplanets, -moons, -comets
Distinguishing N2-Dominated from O2-Dominated Atmospheres on Terrestrial Exoplanets with Reflected-Light Spectroscopy
[astro-ph.EP] Reflected-light spectra of Earth-sized exoplanets promise to probe habitability and biosignatures, but interpreting atmospheric oxygen can be challenging because O2 can arise from both biological and abiotic processes.
Posted inComets and Asteroids
Uncertainty Estimation of Incoming Comet Trajectories with a Thermophysical Non-gravitational Force Model for Comet Interceptor Encounter Planning
[astro-ph.EP] The European Space Agency Comet Interceptor mission is designed to fly-by an as-yet undetermined incoming long-period or dynamically-new comet, which will require an accurate prediction of its trajectory.
Posted inExoplanets, -moons, -comets
Completeness And Dynamical Stability In Exoplanet Occurrence Rates
[astro-ph.EP]. Exoplanet population studies are often quantified through the “occurrence rate” of certain types of planet.
![Colour-magnitude diagram of the 1284 CNS5 stars within 15 pc. Triangles are stars with colours, magnitudes or known spectral types inconsistent with M dwarfs. Empty circles are stars compatible with M stars but without known spectral type in the literature. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/11/Searching.png?resize=1200%2C719&ssl=1)
Posted inStellar Cartography
Searching for Substellar Companion Candidates with Gaia. V. M dwarfs Within 15 pc Studied with Absolute Astrometry, Radial Velocities, and Direct Imaging
[astro-ph.EP] In this work, we survey M-type stars within 15 pc observed by Gaia based on their colour, magnitude, and quality of astrometric data.