The upper atmospheres of temperate sub-Neptunes are strongly influenced by atmospheric dynamics due to their cool equilibrium temperature and thereby longer chemical timescales than the atmospheric dynamical timescales.
astro-ph.EP]
Posted inAtmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Habitable Zones, Icy Worlds, Status Report, Terraforming & Geoengineering, Water/Hycean Worlds & Oceanography
Climate And Ocean Circulation Changes Toward A Modern Snowball Earth
It has been hypothesized that the Earth may have experienced snowball events in the past, during which its surface became completely covered with ice. Previous studies used general circulation models […]
Posted inAstrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Comets and Asteroids, Icy Worlds, Imaging & Spectroscopy, Meteorites & Asteroids, Missions & Hardware, Planetary Protection & Biosafety, Sample Return, Status Report
Tianwen-2 Target Asteroid (469219) Kamo’oalewa Probably Develops An Itokawa-compositional But Ultra-highly Space-weathered Surface
China’s Tianwen-2 mission plans to return samples from a small, rapidly spinning Earth quasi-satellite (469219) Kamo’oalewa. Previous studies linked Kamo’oalewa to lunar composition and origin.
Posted inAstronomy & Telescopes, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report, Stellar Cartography
Automatic Search For Transiting Planets In TESS-SPOC FFIs With RAVEN: Over 100 Newly Validated Planets And Over 2000 Vetted Candidates
Space-based missions such as TESS are identifying a wealth of short-period (≲30 d) transiting planets. Despite the growing number of confirmed and candidate planets, the sample is still incomplete and […]
Posted inAstrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Exploration Gear & Tech, Imaging & Spectroscopy, Status Report
High-resolution mid-IR Spectroscopy of SVS 13-A with EXES/SOFIA: The Surprisingly High CH3OH/H2O Ratio In The Planet-forming Zone Of A Solar Mass Protostar
Water and methanol are key components of interstellar ices and gas in star- and planet-forming regions, but direct observations of water in low-mass protostars are challenging due to atmospheric absorption.
Posted inAstrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report
exoALMA. XXIV. Formaldehyde Emission in Protoplanetary Disks of exoALMA Compared with Their Properties and Dynamical State
The presence of asymmetries and substructures in protoplanetary disks, revealed by both dust and gas emission, highlights the potential interplay and the broader connection between chemistry and dynamics in disk […]
Posted inAstrogeology, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Europa, Habitable Zones, Icy Worlds, Imaging & Spectroscopy, Mapping, Geodesy, Cartography, Bathymetry, Status Report
Spectral Decomposition Reveals Surface Processes on Europa
Competing processes shape Europa’s surface: geological activity replenishes material through resurfacing, while bombardment by charged particles alters surface chemical composition. Each process leaves distinct spectral signatures.
Posted inAtmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Habitable Zones, Status Report
On The Dual Nature Of Atmospheric Escape
Planetary atmospheres cannot remain hydrostatic at all altitudes because they approach finite density at infinite radius, implying infinite mass. Classical treatments address this in two directions: either retain a hydrostatic […]
Posted inAstronomy & Telescopes, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Habitable Zones, Mars, Status Report
Atmospheric Escape Rates from Mars – If it Orbited an Old M-Dwarf Star
Atmospheric escape is an important process that influences the evolution of planetary atmospheres. A variety of physical mechanisms can contribute to escape from an atmosphere, including thermal escape, ion escape, […]
Posted inBiosignatures & Paleobiology, Dione, Enceladus, Icy Worlds, Mapping, Geodesy, Cartography, Bathymetry, Mimas, Missions & Hardware, Press Release, Rhea, Saturn, Tethys, Water/Hycean Worlds & Oceanography
Low-Energy and Low-Thrust Exploration Tour of Saturnian Moons with Full Lunar Surface Coverage
This study presents the trajectory design for a mission touring Saturn’s Inner Large Moons (Rhea, Dione, Tethys, Enceladus, and Mimas) engineered to meet observational requirements, including full surface coverage, while […]