[astro-ph.EP] Given their abundance and observational advantages, M stars will arguably be the best candidates for characterizing and searching for biosignatures on terrestrial exoplanets in the near future.
astro-ph.EP
Posted inExoplanets, -moons, -comets
Finding Habitable Exoplanets with Binary Relative Astrometry: Planet Detection and Characterization with the Microarcsecond Astrometric Retrieval Algorithm (MARA)
[astro-ph.EP] Binary relative astrometry is a technique to search for rocky planets in the habitable zone of nearby binary stars using 1D relative astrometry at the microarcsecond level.
![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 […]
![HZ and planetary orbits in the GJ 12 system. The extent of the HZ is shown in green, where light green and dark green indicate the CHZ and OHZ, respectively. The solid line shows the orbit with the nominal eccentricity of 0.24, and the dashed lines represent 1σ boundaries (Turner et al. 2026). The scale of the figure is 0.2 AU along each side with a 0.02 AU grid.-- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/The-Tidal-.png?resize=1200%2C712&ssl=1)
Posted inExoplanets, -moons, -comets
The Tidal Venus Phenomenon: Demographics and Case Studies
[astro-ph.EP] The demographics of terrestrial planets and their orbits reveal a vast diversity in overall planetary energy budgets.
Posted inAtmospheres, Climate, Weather
A Search for Helium in the Atmospheres of Three Sub-Neptunes and a Super-Earth Around M-dwarfs
[astro-ph.EP] Thousands of sub-Neptunes have been discovered mainly through space-based surveys such as Kepler and TESS. Their bulk compositions and internal structures are thought to reflect their formation and evolutionary […]
![(Top) Measured OC albedo values from Goldstone (from Table 4) and (bottom) measured OC albedo values from the GBT (from Table 5). The horizontal dashed lines indicate the weighted means of the albedos, which is 0.90 for Goldstone and 0.80 for GBT. The error bars on our albedo values are taken to be the total uncertainty calculated in Section 4. The color bar on the right shows the dates of our observations in YYMMDD. The x-axis is the subradar point west longitude. -- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Radar-observations.png?resize=1200%2C751&ssl=1)
Posted inEuropa
Radar Observations Of Europa in 2011-2024: New Insights Into Radar Scattering Properties
[astro-ph.EP] Three of Jupiter’s Galilean satellites – Europa, Ganymede, and Callisto – are of particular scientific interest due to their icy shells and suspected subsurface oceans. However, the radar properties […]
Posted inStellar Cartography
A High-Resolution Spectroscopic Survey of Directly Imaged Companion Hosts: III. Characterization of the Cold Imaged Planet Hosts AF Lep A and ε Indi A
[astro-ph.EP] JWST has enabled the measurement of carbon, oxygen, and sulfur abundances in the atmospheres of directly imaged planets. Interpretation of these abundances from a planet formation standpoint requires the […]
Posted inHabitable Zones
The Viability of Life in Helium-Dominated Exoplanet Atmospheres
[astro-ph.EP] Helium is the second most abundant element in the Universe, yet helium-dominated atmospheres are rarely considered as environments for life.
Posted inEnceladus
The Enceladian Crater Production Function
[astro-ph.EP]. Interpreting Enceladus’s past and present surface history and interior state remains challenging, owing to uncertain prescription of its impact bombardment history and limited interpretation of its crater statistics. Further […]
![CI mass as a function of radial distance from the host star, for a continuum of solid surface densities. Over-plotted is the FI1 mass (𝑀¤ = 10−9 M⊙ yr−1 ) for a continuum of maximum Stokes numbers, as well as the MFI1 (opaque purple) and MFI2 (dashed red) masses and the PI mass (dotted black). The last three show no continuum of mass distributions, since we vary their initial mutual Hill spacing within the simulation. Thus, all initial simulations begin from the same mass distribution model, albeit with a different number of embryos at different spacings.-- [astro-ph.EP]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/Effects-of-Pebble.png?resize=1200%2C715&ssl=1)
Posted inExoplanets, -moons, -comets
Effects Of Pebble Accretion Isolation Mass On Observable Exoplanet Properties
[astro-ph.EP] The Kepler Mission has discovered a plethora of planetary systems with super-Earth sized planets.