ice shell Archives

Coordinate systems. (a) Schematic of the coordinate systems. e𝜃 and er are the meridional (latitudinal) direction and the vertical direction (opposite to the gravitational direction), respectively. ez and es are the axial direction aligned with planetary rotation and the radial direction perpendicular to it, respectively. e𝜙 represents both the zonal direction in spherical coordinates and the azimuthal direction in cylindrical coordinates. (b) Distribution of 𝐻𝑧 in the simulation with Enceladus-like parameters: a core radius of 192 km and an ocean surface radius of 232 km. Outside the tangent cylinder, 𝐻𝑧 is kept constant. In (a) and (b), gray dashed lines indicate the tangent cylinder. -- astro-ph.EP

Astrogeology, Exoplanets, -moons, -comets, Icy Worlds, Water/Hycean Worlds & Oceanography

Parameterizing Slantwise Convection In Icy Moon Oceans

by Keith CowingJune 25, 2026June 25, 2026

Convection in icy moon oceans is strongly influenced by rotation, organizing into slantwise columnar structures aligned with the planetary rotation axis. They generate significant meridional heat transport, which can affect […]

Previous vs. current microbe-integrated ocean world model setups. Previous models (left) include ambient temperatures, hydroxide effluent, circumneutral pH's, and effluent-bacteria integration (Barge et al., 2015; Hermis et al., 2021; Dickson et al., 2022). This study (right) includes thermal gradients, FeOOH/sulfide rich effluent (brine fluid), acidic reservoir pH, and planktonic lake extremophile integration. -- Frontiers

Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Cryobiology, Europa, Extremeophiles and Extreme Environments, Genomics, Proteomics, Bioinformatics, Microbiology & Virology, Origin & Evolution of Life, Press Release

Probing The Habitability Of Potential Sulfuric Acid Rich Subsurface Lakes In Europa’s Ice Shell Via Saci/STIV Integrated Models

by Keith CowingJune 21, 2026June 21, 2026

Experimentally modeling the habitability of extreme ocean world conditions, such as those on Jupiter’s moon: Europa, would benefit from integrated microbe-virus model studies to provide both a microbial model and […]

Schematic overview of the interior model of Trappist1f,g,h. The ice I layer is divided into a conductive and a convective sublayer. The thermal model determines the thickness of the conductive and convective layers, Rice,I , RHPI, and Qeq. The tidal model computes the tidal heating rates in the HPI, and the mantle. The layer boundaries are not to scale. Note that the convective layer -- astro-ph.EP

Astrogeology, Astronomy & Telescopes, Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Icy Worlds, Imaging & Spectroscopy, Press Release, TRAPPIST-1, Water/Hycean Worlds & Oceanography

Interior-Atmosphere Coupling on TRAPPIST-1 f, g, and h: Cryovolcanic Water Exospheres and Infrared Detectability

by Keith CowingMay 28, 2026May 28, 2026

We investigate the interior structures and cryovolcanic observability of the exoplanets TRAPPIST-1f, g, and h. Our aim is to determine which interior configurations can sustain subsurface liquid water oceans in […]

Discrete mesh for the 3-D model with a heterogeneous ice shell thickness. The ice shell surface and base are constrained by models depicted in Figure 1 and described in Table 1. The yellow circle depicts the ice base of the mean ice shell, corresponding to the 1-D model. Three colors denote ice, ocean, and core regions. Each region is assigned a homogeneous electrical conductivity according to Table 2. The total number of cells in the mesh is 126976. -- astro-ph.EP

Astrogeology, Biogeochemical Cycles & Geobiology, Enceladus, Icy Worlds, Imaging & Spectroscopy, Mapping, Geodesy, Cartography, Bathymetry, Press Release

Exploring Enceladus’s Interior Structure Using Electromagnetic Induction

by Keith CowingMay 13, 2026May 13, 2026

Electromagnetic (EM) sounding can constrain the electrical structure of Enceladus and, in turn, the salinity of its ocean and the porosity, fluid content, and thermal state of its hydrothermally active […]

(A) Schematic of the ice growth apparatus. (B) Image of the ice growth apparatus shortly after the onset of an experiment. (C) The ~50-cm-thick Europa 2 ice column immediately after extraction. The column is placed upside down to reduce brine loss from the highly porous basal region of the ice. (D) Ice columns subsectioned into smaller, more easily workable pieces and scored at 2-cm intervals in preparation for vertical partitioning. (E) The scored subsections in (D) were cut using an electric band saw, and the 2-cm layers were placed into 500-ml high-density polyethylene amber Nalgene sample bottles. These samples were subsequently melted, filtered, and processed via IC, ICP-OES, and NDIR spectroscopy to acquire our ionic composition and ionic fractionation profiles. -- Science Advances via PubMed

Analog Studies, Arctic / Antarctic / Alpine, Astrogeology, Biogeochemical Cycles & Geobiology, Cryobiology, Enceladus, Europa, Exploration Gear & Tech, Ganymede, Icy Worlds, Mapping, Geodesy, Cartography, Bathymetry, Polar / Alpine Expeditions, Robotics/Rovers/UAVs, Status Report, Water/Hycean Worlds & Oceanography

As Above, Not So Below: Ion Fractionation In Planetary Analog Ices

by Keith CowingApril 25, 2026April 25, 2026

The geophysical evolution and astrobiological potential of ocean worlds are indelibly linked to the chemical compositions of their oceans and ice shells.

Numerical solutions for the three high-diffusivity

Astrogeology, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Enceladus, Icy Worlds, Imaging & Spectroscopy, Saturn, Status Report, Water/Hycean Worlds & Oceanography

Subsurface Ocean Salinity And Dissipation Rate Inferred From Enceladus Ice Shell Morphology

by Keith CowingMarch 31, 2026March 31, 2026

The habitability of Enceladus’ subsurface ocean and the detectability of potential biosignatures depend on efficient ocean circulation and suitable ocean conditions.

The 0.6-GHz data are much brighter due to reflected synchrotron emission and are, therefore, shown with a different colour scale. The terminator was at approximately 10° W longitude, with the right-hand side in sunlight for these maps. The approximate sounding depth (50% contribution for pure, solid ice) is shown in the lower right of each map, and a typical beam size is shown in the lower left of each map. -- Nature

Analog Studies, Astrogeology, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Europa, Habitable Zones, Icy Worlds, Imaging & Spectroscopy, Status Report

Europa’s Ice Thickness And Subsurface Structure Characterized By The Juno Microwave Radiometer

by Keith CowingJanuary 5, 2026January 2, 2026

Jupiter’s moon Europa is thought to harbour a saltwater ocean beneath a variously disrupted ice shell, and it is, thus, one of the highest priority astrobiology targets in the Solar […]

Saturn's moon Mimas, imaged by the Cassini spacecraft. A new study shows how such small ice moons could sustain a liquid ocean beneath an icy shell, and how that could give rise to surface features. Credit By NASA / JPL-Caltech / Space Science Institute

Enceladus, Icy Worlds, Mimas, Miranda, Press Release, Titania

Looking Inside Icy Moons

by Keith CowingNovember 25, 2025November 25, 2025

The outer planets of the Solar System are swarmed by ice-wrapped moons. Some of these, such as Saturn’s moon Enceladus, are known to have oceans of liquid water between the […]

The Radar for Europa Assessment and Sounding: Ocean to Near-surface (REASON) PubMed

Arctic / Antarctic / Alpine, Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Cryobiology, Europa, Icy Worlds, Mapping, Geodesy, Cartography, Bathymetry, Missions & Hardware, Robotics/Rovers/UAVs, ROVs/Submersibles/Diving, Status Report, Water/Hycean Worlds & Oceanography

Europa Clipper: Radar for Europa Assessment and Sounding: Ocean to Near-Surface (REASON)

by Keith CowingSeptember 22, 2024September 22, 2024

The Radar for Europa Assessment and Sounding: Ocean to Near-surface (REASON) is a dual-frequency ice-penetrating radar (9 and 60 MHz) onboard the Europa Clipper mission. REASON is designed to probe […]