astro-ph.EP Archives

Kp – Vsys maps for species which we claim a detection or a tentative detection in HAT-P-70b’s atmosphere with 2 transits from the MAROON-X spectrograph. White dashed lines indicate the expected position of the signal, assuming a symmetric planet with a static atmosphere. Peaks of the cross-correlation function are shown as white regions near the expected position. The peaks show a slight offset in Vsys, indicative of the presence of strong winds in the atmosphere. The standard deviation is calculated with from a box delimited by Vsys = −100 km s−1 and Vsys = 0 km s−1 -- astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Gas Giants, Habitable Zones, Imaging & Spectroscopy, Status Report

HAT-P-70b Through The Eyes of MAROON-X: Constraining Elemental Abundances of Metals and Insights on Atmosphere Dynamics

by Keith CowingMay 13, 2026May 13, 2026

Ultra-hot Jupiters (UHJs) are exceptional laboratories for studying planetary atmospheres under extreme irradiation conditions.

TOP Ice states for HEXTOR calculations based on the THAI Hab 1 configuration, which show smooth transitions from ice-covered to cool dayside to warm dayside to ice-free states as instellation increases. These results do not depend on the choice of initialization temperature. BOTTOM Ice states for HEXTOR calculations based on the THAI Hab 1 configuration, across a parameter space of instellation and CO2 partial pressure. -- astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Gaia - Planetary Perspectives, Imaging & Spectroscopy, Status Report, TRAPPIST-1, Water/Hycean Worlds & Oceanography

Exploring TRAPPIST-1 Climate States With An Energy Balance Model

by Keith CowingMay 12, 2026May 12, 2026

This paper presents a version of the HEXTOR energy balance model that has been configured for the study of habitable terrestrial planets orbiting low-mass stars. The model is validated for […]

Probability of a planet with initial semi major axis a0 remaining bound to its host star after the birth cluster dissolves as a function of absolute value of the angular separation |∆ϕ| from the centre of the stream. Contours of Psurvive are determined after applying a multidimensional Gaussian filter to the dataset with a standard deviation of 1. Stars close to the centre of the stream are less likely to host planets at any a0, with outer planets more likely to be stripped from their host star than inner planet. Stars near the edges of the stream are more likely to retain planets out to 2000 au. -- astro-ph.EP

AI - Data - Apps - Cybernetics, Exoplanets, -moons, -comets, Status Report, Stellar Cartography

Life Is But a Stream: The Distribution Of Planetary Systems Along Stellar Streams And Their Properties

by Keith CowingMay 11, 2026May 11, 2026

The majority of discovered exoplanets have been observed orbiting field stars as opposed to within a star cluster. To determine whether the lack of observed exoplanets in star clusters is […]

This image shows the MINERVA-Australis array located at the Mount Kent Observatory in Australia. -- NASA

Astronomy & Telescopes, Exoplanets, -moons, -comets, Status Report, Stellar Cartography

Finding Alien Worlds in Queensland — A Decade of MINERVA-Australis

by Keith CowingMay 9, 2026May 9, 2026

Three decades ago, humanity entered the Exoplanet Era, with the discovery of the first planets orbiting other stars. Today, more than 6000 exoplanets are known – a tally recently bolstered […]

Interior pressure profiles as a function of depth for rocky bodies with varying surface gravities.

Astrogeology, Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Imaging & Spectroscopy, Lava / magma ocean / Volcanic Worlds, Mars, Status Report, TRAPPIST-1, Venus

Modeling Volcanic Plume Heights Across Exoplanet Atmospheres: Insights from TRAPPIST-1

by Keith CowingMay 8, 2026May 8, 2026

Explosive volcanic eruptions play a fundamental role in the evolution and observability of rocky exoplanets, serving as a key mechanism for injecting volatiles into planetary atmospheres and potentially modifying their […]

Flux-calibrated, continuum-subtracted optical spectra of comets 67P and 103P observed from HCT on November 9, 2021, and September 28, 2023, respectively, extracted within a 60" aperture centered on the comet. -- astro-ph.EP

Astrochemistry, Astrogeology, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Status Report

Activity And Composition of Periodic Comets 67P/Churyumov-Gerasimenko and 103P/Hartley 2 At Two Different Perihelion Passages

by Keith CowingMay 8, 2026

Through photometry and spectroscopy, we studied the evolution of the activity and chemical composition of comet 67P during its 2025 and 2021 perihelion passages and of comet 103P during its […]

Three station light curves of 2002 XV93’s stellar occultation on 10 January 2024. The flux points (points with error bars) observed at Kyoto (a), Kiso (b) and Fukushima stations (c) overlaid with the synthetic light curves (red lines, assuming a pure CH4 atmosphere and a best-fit surface pressure of 124 nanobars) are shown as a function of time. In panel c, the gray points are the flux points for the individual exposures, and the black points are those binned by a factor of 8. The vertical arrow represents the closest approach time to the shadow edge at Fukushima, at 13:12:50.818 UT. -- astro-ph.EP

Astrochemistry, Astronomy & Telescopes, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Icy Worlds, Imaging & Spectroscopy, Pluto, Status Report

The First Detection Of An Atmosphere On A Trans-Neptunian Object Beyond Pluto

by Keith CowingMay 8, 2026May 8, 2026

Trans-Neptunian objects (TNOs) in the outer Solar System are predominantly small, icy worlds long presumed to be atmosphereless except for the largest bodies.

The figure reports two of the PSFs used to simulate FGS1 (left) and AIRS-CH0 (right). The PSFs are sampled at the sub-pixel level and reported in decibels normalised to the maximum value in the field. The axes report the grid into pixel and micron units. The reader may note that the FGS1 PSF is highly aberrated and complex, so it is sampled on a grid of the same size as the detector (32 × 32), while the AIRS-CH0 PSF is an Airy function and here is reported on a smaller grid. For details, please refer to the software documentation. -- astro-ph.EP

AI - Data - Apps - Cybernetics, Ariel Mission, Astronomy & Telescopes, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report, Stellar Cartography

A Public Dataset Of Ariel Simulated Observations For Developing Exoplanetary Atmosphere Data Reduction Pipelines

by Keith CowingMay 7, 2026May 7, 2026

Detecting and characterising exoplanet atmospheres remains challenging because atmospheric signals can be comparable to residual noise and instrumental/astrophysical systematics. Spectral features span from a few ppm for small planets up […]

Relative entropy shift applied by the Mazevet et al. (2019) correction (Eq. (17)) across the water phase diagram in plog10 T, log10 Pq space. The colormap is logarithmic between 10´3 and 10, with the upper bound saturating along a narrow ridge where the aqua baseline entropy nearly vanishes. Solid white lines mark the phase boundaries of the underlying aqua table; labels identify the fields of ices, liquid, vapor, and supercritical water. Dashed lime contours with inline labels mark the analytic gate w7 that selects where the patch is applied: w7“0 outside the patch (no shift) and w7“1 inside its core (full correction). The figure shows that the correction is concentrated in a localized strip of the supercritical regime between ice X and the Brown (2018) fluid, leaving the rest of the aqua table untouched. -- astro-ph.EP

Astrogeology, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Status Report

PALEOS: Multiphase Equations of State and Mass-Radius Relations for Exoplanet Interiors

by Keith CowingMay 7, 2026May 7, 2026

Modeling the interior of a rocky or water-rich exoplanet is a thermodynamic closure problem: every layer’s density, temperature gradient, and phase must follow from an equation of state (EoS) that […]

Two orders of high-resolution spectra with the best-fit model overplotted in yellow for each target. The observation on the first day (September 21, 2022) is chosen for 2MASS J0249-0557 c. The wavelength range is selected to include the 12CO and 13CO bandheads. -- astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Beta Pictoris, Brown Dwarfs, Exoplanets, -moons, -comets, Gas Giants, Status Report

Chemistry And Isotope Ratios Of Substellar Atmospheres In The β Pictoris Young Moving Group

by Keith CowingMay 6, 2026May 6, 2026

Measuring the chemical and isotopic compositions of gas giants and brown dwarfs provides insights into their formation pathways and birth environments. 2MASS J0249-0557 c is an L2-type planetary mass companion […]

astro-ph.EP

HAT-P-70b Through The Eyes of MAROON-X: Constraining Elemental Abundances of Metals and Insights on Atmosphere Dynamics

Exploring TRAPPIST-1 Climate States With An Energy Balance Model

Life Is But a Stream: The Distribution Of Planetary Systems Along Stellar Streams And Their Properties

Finding Alien Worlds in Queensland — A Decade of MINERVA-Australis

Modeling Volcanic Plume Heights Across Exoplanet Atmospheres: Insights from TRAPPIST-1

Activity And Composition of Periodic Comets 67P/Churyumov-Gerasimenko and 103P/Hartley 2 At Two Different Perihelion Passages

The First Detection Of An Atmosphere On A Trans-Neptunian Object Beyond Pluto

A Public Dataset Of Ariel Simulated Observations For Developing Exoplanetary Atmosphere Data Reduction Pipelines

PALEOS: Multiphase Equations of State and Mass-Radius Relations for Exoplanet Interiors

Chemistry And Isotope Ratios Of Substellar Atmospheres In The β Pictoris Young Moving Group

NASA Spaceline Current Awareness List #1,215 4 September 2026 (Space Life Science Research Results)

The Metallicity Of Giant Exoplanets Around Low-mass Stars And How Ariel Can Help

Two Extremely Irradiated Volatile-rich Sub-Neptunes With Companions In The TOI-426 And TOI-1839 Systems: Insights Into Arrival And Survival Near The Lower Edge Of The Neptunian Desert

Mapping the WISPIT2 Planet-Hosting Cavity at Sub-Hill-Radius scales

Contrasting C/O Ratios in Uranus and Neptune From Disequilibrium Chemistry: A Clue To Distinct Evolutionary Pathways?