Related papers: Europa's Surface Water-ice Crystallinity and Corre…
Brinicles are self-assembling tubular ice membrane structures, centimeters to meters in length, found beneath sea ice in the polar regions of Earth. We discuss how the properties of brinicles make them of possible importance for chemistry…
Europa's icy surface likely overlies an ocean, but the ice thickness is not known. Here we model the temporal growth of a Europan shell of pure ice subject to varying ice-ocean heat fluxes, ice rheologies, and internal heating rates. Both…
Thermal measurements constrain the physical properties of icy satellite surfaces, including grain size, porosity, and regolith structure. On Europa, analyses of the Galileo Photopolarimeter-Radiometer (PPR) dataset revealed thermal inertia…
H$_2$O$_2$ is part of Europa's water-ice radiolytic cycle and a potential source of oxidants to Europa's subsurface ocean. However, factors controlling the concentration of this critical surface species remain unclear. Though laboratory…
The crystallinity of water ice not only records the thermal history experienced by an astronomical body, but also affects the composition of forming planets by controlling the trapping of volatile materials in amorphous ice and their…
We present results from Keck II observations of Europa over four consecutive nights using the near-infrared spectrograph (NIRSPEC). Spectra were collected in the 3.14--4.0 micron range, allowing detection and monitoring of the 3.5 micron…
Europa, Jupiter's second Galilean moon, is believed to host a subsurface ocean in contact with a rocky mantle, where hydrothermal activity may drive the synthesis of organic molecules. Of these molecules, abiotic synthesis of aromatic amino…
The circulation in Europa's ocean determines the degree of thermal, mechanical and chemical coupling between the ice shell and the silicate mantle. Using global direct numerical simulations, we investigate the effect of heterogeneous tidal…
Europa is an icy ocean world, differentiated into a floating ice shell and solid interior, separated by a global ocean. The classical spin-orbit coupling problem considers a satellite as a single rigid body, but in the case of Europa, the…
Much of the geologic activity preserved on Europa's icy surface has been attributed to tidal deformation, mainly due to Europa's eccentric orbit. Although the surface is geologically young (30 - 80 Myr), there is little information as to…
We publish the first NIR spectra of grain particulate mixtures of water ice, epsomite, and halite at cryogenic temperatures. Furthermore, we perform a quantitative assessment of the ability of both intimately- and linearly-mixed models to…
We present maps of Ganymede's surface composition with almost complete longitude coverage, acquired using high spatial resolution near-infrared (0.95 to 1.65$\mu m$) observations from the ground-based VLT/SPHERE instrument. Observed…
Europa's leading hemisphere chaos regions have a spectral feature at 450 nm that has been attributed to absorption by crystal defects in irradiated sodium chloride, known as F-centers. Some discrepancies exist between the laboratory data of…
The microscopic mechanisms controlling heterogeneous ice nucleation are complex and remain poorly understood. Although good ice nucleators are generally believed to match ice lattice and to bind water, counter examples are often identified.…
The composition of Europa's trailing hemisphere reflects the combined influences of endogenous geologic resurfacing and exogenous sulfur radiolysis. Using spatially resolved visible-wavelength spectra of Europa obtained with the Hubble…
Jupiter's icy moons are believed to host subsurface liquid oceans, and among them, Europa stands out as one of the most promising candidates for extraterrestrial life. Yet, the processes driving oceanic flows beneath its ice shell, as well…
In the absence of direct observations of Europa's particle plumes, deposits left behind during eruptive events would provide the best evidence for recent geological activity, and would serve as indicators of the best places to search for…
The presence of NH$_3$-bearing components on icy planetary bodies has important implications for their geology and potential habitability. Here, I report the detection of a characteristic NH$_3$ absorption feature at 2.20 $\pm$ 0.02 $\mu$m…
The distribution of ions at the air/water interface plays a decisive role in many natural processes. It is generally understood that polarizable ions with low charge density are surface-active, implying they sit on top of the water surface.…
Despite the ubiquity of ice, a molecular-resolution image of ice crystallized from liquid water or the resulting defect structure has never been obtained. Here, we report the stabilization and angstrom-resolution electron imaging of ice Ih…