icy world Archives

An artist's rendering of Europa and Jupiter based on images sent by visiting spacecraft. Europa is the closest orbiting of the three Jupiter’s large ‘Galilean’ moons to be visited by Juice – any human astronaut that lands there would receive a lethal radiation dose on a timescale of hours. And spacecraft electronics are almost as susceptible to radiation as human biology. CREDIT NASA/JPL-Caltech

Europa, Meteorites & Asteroids, Origin & Evolution of Life, Panspermia, Planetary Protection & Biosafety, Status Report, Water/Hycean Worlds & Oceanography

Earth As A Potential Source Of Llife For Europa’s Subsurface Ocean

by Keith CowingJune 22, 2026June 21, 2026

The paper discusses the possibility of dust particles containing living bacteria ejected from Earth reaching Europa and landing on its surface.

Panels (a)–(o) show contour maps of the observed isophotes (black lines) together with the corresponding modelled isophotes (red lines) for the case 𝑟max = 1 cm. For each of these contour panels, a companion plot is displayed to the right, labelled (a′ )–(o′ ), showing a one-dimensional scan extracted along the direction indicated by the straight red line in the corresponding contour map. In these primed panels, the black and red curves represent the observed and modeled brightness profiles, respectively. The 𝑥- and 𝑦-axes in the contour plots are given in pixel units, and the innermost isophote levels as well as the physical dimensions of each image are listed in Tables 1 and 3. In panels (a)–(o), isophote levels increase outward in steps of 1 mag. In the primed panels, the 𝑥-axis is expressed in pixel units and the 𝑦-axis in surface brightness units (mag arcsec−2). -- astro-ph.EP

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

Dust Colour, Phase Behaviour, And Monte Carlo Modelling Of Interstellar Comet 3I/ATLAS From 4 au Pre- to 4 au Post-Perihelion

by Keith CowingJune 19, 2026June 19, 2026

We report multi-band photometric imaging observations and Monte Carlo dust tail modelling of the interstellar comet 3I/ATLAS covering a wide range of heliocentric distances, from about 4 au pre-perihelion to […]

This artist's impression shows radar waves from the NASA Goldstone Solar System Radar pinging one of Jupiter’s moons, Europa. The radar waves penetrate Europa’s icy surface before bouncing back to be collected by the NSF Green Bank Telescope on Earth. Credit: NSF/AUI/NSF NRAO/P.Vosteen

Callisto, Europa, Ganymede, Habitable Zones, Icy Worlds, Journal articles, Press Release, Water/Hycean Worlds & Oceanography

Radar Echoes From Europa Reveal Secrets Beneath the Ice

by Keith CowingJune 18, 2026June 18, 2026

A team of scientists has used NASA’s Goldstone Solar System Radar and the U.S. National Science Foundation Green Bank Telescope (NSF GBT) to carry out the most extensive radar study […]

ID: ESP_087131_2640 date: 26 February 2025 altitude: 316 km larger image

Astrogeology, Biogeochemical Cycles & Geobiology, Desert Worlds, Icy Worlds, Imaging & Spectroscopy, Mars, Status Report

The Spring Awakening of Martian Polar Dunes

by Keith CowingJune 16, 2026June 16, 2026

During the Martian winter, carbon dioxide ice (dry ice) blankets various landforms, including dunes, in the northern high latitudes. As spring arrives, the ice sublimates, causing unique changes on the […]

An artist’s rendition of Saturn’s moon Enceladus depicts hydrothermal activity on the seafloor and cracks in the moon’s icy crust that allow material from the watery interior to be ejected into space. New research shows that instruments destined for the next missions could find traces of a single cell in a single ice grain contained in a plume. NASA/JPL-Caltech

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Enceladus, Habitable Zones, Icy Worlds, Status Report

Tidal Rock Grinding As A Source Of H2 On Enceladus

by Keith CowingJune 16, 2026June 16, 2026

The Solar System hosts multiple potentially habitable environments, including the subsurface ocean beneath the icy crust of Saturn’s moon Enceladus.

a, Sub-ice topography, corrected for isostatic rebound due to ice removal3, with sharp topographic features enhanced by nonlinear filtering (Methods). The light grey lines are detected topographic lineaments interpreted as longitudinal normal faults forming the structural edges of the basins. The magenta and cyan lines represent detected topographic lineaments interpreted as either transverse strike–slip faults or associated normal faults that characterize the two circular shear belts shown in b (that is, the southern and northern TSCBs).

Analog Studies, Arctic / Antarctic / Alpine, Biogeochemical Cycles & Geobiology, Caves, Craters, Mountains, Subsurface, Lava Tubes, Exploration Gear & Tech, Gaia - Planetary Perspectives, Habitable Zones, Icy Worlds, Imaging & Spectroscopy, Mapping, Geodesy, Cartography, Bathymetry, Polar / Alpine Expeditions, Press Release, Water/Hycean Worlds & Oceanography

Ice Planet Recon: Giant Fan-shaped Geological Structure Discovered Beneath East Antarctica

by Keith CowingJune 9, 2026June 26, 2026

Editor’s note: there are currently two advanced missions heading for the jovian system – Europa Clipper and ESA Juice – to study icy Europa and the other icy worlds orbiting […]

Locations (yellow circles) of ROIs that include paterae, potential flows, and cryovolcanic candidate regions (K. Stephan et al. 2021a) on top of the global geological map of Ganymede from G. C. Collins et al. (2013). Mercator projection. -- The Planetary Science Journal

Astrogeology, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Ganymede, Habitable Zones, Icy Worlds, Imaging & Spectroscopy, Mapping, Geodesy, Cartography, Bathymetry, Missions & Hardware, Status Report

Potential Cryovolcanic Regions on Ganymede: A Priority Target for JUICE

by Keith CowingJune 7, 2026June 26, 2026

One of the Jupiter Icy Moons Explorer (JUICE) mission goals of the European Space Agency, launched in 2023 April, is the detailed characterization of Ganymede, Jupiter’s largest moon and a […]

Allen Telescope Array (ATA) at the Hat Creek Radio Observatory in Northern California -- SETI Institute

Astrochemistry, Astronomy & Telescopes, Biosignatures & Paleobiology, Comets and Asteroids, Imaging & Spectroscopy, Intelligence & Language, Interstellar, Press Release, SETI & Technosignatures

SETI Institute Looks for Signs of Technology in Interstellar Visitor 3I/ATLAS

by Keith CowingJune 4, 2026June 4, 2026

Scientists at the SETI Institute searched for technological signals from 3I/ATLAS, the third interstellar object observed in our Solar System.

Examples of materials with extremely high porosities (ϕ > 80%). a) Heesch & Laves (1933) 94.45% rigid packing structure. b) and c) pictures from Blum & Schr¨apler (2004) experiments of SiO2 agglomerates with 85% porosity. d) Water ice aggregates with 89% porosity observed with a long-distance microscope (Gundlach et al. 2011). Bottom Row: experimental pictures from the Core-Mantle Particle Sedimentation System e) Cryogenically cooled chamber with 15 mm high needles that serve as sample mounts for ice aggregates. f) Micrometer-sized water ice spheres as seen from the scanning electron microscope. g) Fractal ice aggregates as seen from the long distance microscope. Each individual grain has been highlighted in yellow on the right side of the picture. -- astro-ph.EP

Astrochemistry, Astrogeology, Icy Worlds, Imaging & Spectroscopy, Status Report

The Physical Nature of Regolith on Icy Moons

by Keith CowingMay 28, 2026May 28, 2026

Estimating surface properties such as porosity and grain sizes is key for planning lander missions and landing site selection on icy moons.

Spectral characterization of Chiron’s surface composition. a Comparison of the bestfit spectral model of the surface composition (red) with the measured spectrum (black). The surface is best described by an intimate mixture of water ice in both amorphous and crystalline phases, carbon dioxide ice, and tholin-like materials. b Residuals between the model and the data show an excellent fit, with a root mean square deviation that is just 1% higher than the average scatter in the data. c Zoomed-in view of the complex organic absorption feature spanning 3.3–3.6 µm, with the individual component bands indicated by dashed lines. Comparison between the measured spectrum and synthetic spectra of several candidate species, convolved to the spectral resolution of the data, points to C3H8 and/or ice tholins produced by the irradiation of H2O ice and C2H6 as the most plausible candidates for the observed organic feature. -- astro-ph.EP

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

JWST Reveals Anomalously Enhanced Methane Outgassing From Below Chiron’s Water Ice And Carbon Dioxide Bearing Surface

by Keith CowingMay 26, 2026May 26, 2026

Centaurs are inward-scattered Kuiper belt objects, with some exhibiting comet-like activity. The physical mechanisms powering this activity remain poorly understood, with carbon monoxide (CO) sublimation or the crystallization of amorphous […]