ocean Archives

Magnetic field components in the xy-plane in the ocean-reservoir environment after mutual induction coupling for a reservoir with radius rres = 20 km and finite conductivity σres = 30 S/m, where the induction response of the system follows equation 19. The arrows representing the magnetic field are normalized in length and do not represent the strength of the magnetic field, which is instead color coded in the background. The arrows in the center indicate the orientations of the background field (black), ocean induced field (green), and reservoir induced field (cyan), where the length indicates the strength relative to the background field. The dashed black line visualizes the surface boundary. -- astro-ph.EP

Astrogeology, Europa, Habitable Zones, Status Report, Water/Hycean Worlds & Oceanography

Detectability Of Local Water Reservoirs In Europa’s Surface Layer Under Consideration Of Coupled Induction

by Keith CowingOctober 10, 2023October 9, 2023

The icy moon Europa is a primary target for the study of ocean worlds. Its subsurface ocean is expected to be subject to asymmetries on global scales (tidal deformation) and […]

Values of (a) ice-ocean heat flux and (b) thickness under which a conductive steady state is expected at particular basal viscosities in an ice shell with no internal heat source. The Rayleigh number is shown in color; here the critical Rayleigh number is taken to be 106 . The white section of the color plot in (b) as well as in (c) corresponds to the region for which steady-state conductive thicknesses would exceed the critical Rayleigh number. (c) Values of ice-ocean heat flux and thickness (inset) under which a conductive steady state is expected at particular basal viscosities in an internally-heating ice shell (I = 10−6 Wm−3 ). Rayleigh number is in color. Related steady-state conductive thicknesses are shown in the inset.(d) Relationship between ice shell thickness and ice-ocean heat flux for different values of internal heating (color) in steady-state. Depth-dependent internal heating following the prescription in Equation 7 for particular reference viscosities are shown by the black dots (ηb = 1013 Pa s), plus signs (ηb = 1015 Pa s), and stars (ηb = 1017 Pa s). The black dots with the gray outline indicate ice thicknesses which would be unstable to convection for the given reference viscosity and a critical Rayleigh number of O(106 ). -- astro-ph.EP

Astrogeology, Europa, Icy Worlds, Status Report, Water/Hycean Worlds & Oceanography

Europa’s Coupled Ice-Ocean System: Temporal Evolution of a Pure Ice Shell

by Keith CowingOctober 4, 2023October 4, 2023

Europa’s icy surface likely overlies an ocean, but the ice thickness is not known.

3D GCM output at 40◦ obliquity and H2=10% for the rain precipitation, snow and ice fraction at the surface, snowfall, sea/ground surface temperature. Black contour lines represent surface elevation level (-2000, 0, 2000 and 8000 meters) and the red contour line is the paleo-shoreline (-3900 meters). -- astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Mars, Status Report, Water/Hycean Worlds & Oceanography

Circumpolar Ocean Stability On Mars 3 Billion Years Ago

by Keith CowingOctober 3, 2023October 3, 2023

What was the nature of the Late Hesperian climate? Warm and wet or cold and dry? Formulated this way the question leads to an apparent paradox since both options seem […]

Maps of the CO2 n3 band area and the ratio between its two peaks. The disk of Europa is indicated by the black circles in both panels and centered at 2.7°N and 93°W. Gray dashed lines indicate the 45°W, 90°W, and 135°W meridians and the 60°S, 30°S, 0°N, 30°N, and 60°N parallels. The large-scale chaos regions Tara Regio (~10ºS, 75ºW) and Powys Regio (~0ºS, 150ºW) are outlined in black within the disk using the boundaries as defined by (11). (A) Mapped band area (indicated by the color bar) of the entire n3 CO2 band. The strongest absorption occurs in Tara Regio, the region of disrupted terrain centered to the right of the 90°W meridian. CO2 also appears concentrated in parts of the chaos region Powys Regio, which is shown on the left portion of the disk. (B) The mapped ratio between the 4.25-µm and 4.27-µm peaks within the CO2 band. The spatial pixels outlined in white mark the locations of the spectra shown in Figure 1. The 4.25-µm peak is the stronger of the two within the chaos terrain and at low latitudes, while the 4.27-µm peak is stronger in the colder, more ice-rich northern latitudes. -- astro-ph.EP

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Europa, Habitable Zones, Icy Worlds, Imaging & Spectroscopy, Status Report, Water/Hycean Worlds & Oceanography

The Distribution Of CO2 On Europa Indicates An Internal Source Of Carbon

by Keith CowingSeptember 23, 2023September 23, 2023

Jupiter’s moon Europa has a subsurface ocean, the chemistry of which is largely unknown. Carbon dioxide (CO2) has previously been detected on the surface of Europa, but it was not […]

(a) A map of Europa’s trailing hemisphere, showing a selection of four of the 29 considered “rings of constant radiolysis” outlined in black, which are used to determine whether the weak 2.07 µm absorption feature is associated with Europa’s large-scale geologic units. The chaos terrains are shown in red and Pwyll crater and its ejecta are orange. For each ring, projected detector pixels are shown and their assigned geologic unit indicated by color, where chaos terrains are dark red, Pwyll crater and its ejecta are orange, and the ridged plains are gray. (Europa map image credit: NASA/JPL/ Bj¨orn J´onsson). -- astro-ph.EP

Astrogeology, Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Europa, Icy Worlds, Imaging & Spectroscopy, Status Report, Water/Hycean Worlds & Oceanography

The Spatial Distribution of the Unidentified 2.07 μm Absorption Feature on Europa and Implications for its Origin

by Keith CowingAugust 30, 2023August 30, 2023

A weak absorption feature at 2.07 μm on Europa’s trailing hemisphere has been suggested to arise from radiolytic processing of an endogenic salt, possibly sourced from the interior ocean.

Astrogeology, Europa, Icy Worlds, Missions & Hardware, Press Release, Water/Hycean Worlds & Oceanography

Ocean Currents May Affect Rotation of Europa’s Icy Crust

by Keith CowingMarch 13, 2023March 13, 2023

Research reveals a new explanation for how the icy shell of Jupiter’s moon Europa rotates at a different rate than its interior. NASA’s Europa Clipper will take a closer look.

Astrogeology, Enceladus, Icy Worlds, Press Release

How Enceladus Ejects Particles From Oceans Beneath Its Surface

by Keith CowingFebruary 23, 2023February 23, 2023

Although it is relatively small, Enceladus — the sixth largest of Saturn’s 83 moons — has been considered by astronomers to be one of the more compelling bodies in our […]

Astrochemistry, Exoplanets, -moons, -comets, Habitable Zones, Icy Worlds, Meteorites & Asteroids, Status Report, Water/Hycean Worlds & Oceanography

Origin Of Water In The Terrestrial Planets: Insights From Meteorite Data And Planet Formation Models

by Keith CowingFebruary 7, 2023February 7, 2023

Water condensed as ice beyond the water snowline, the location in the Sun’s natal gaseous disk where temperatures were below 170 K. As the disk evolved and cooled, the snowline […]

Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Mars, Press Release, Water/Hycean Worlds & Oceanography

Traces Of An Ancient Ocean Have Been Discovered On Mars

by Keith CowingOctober 28, 2022October 28, 2022

A recently released set of topography maps provides new evidence for an ancient northern ocean on Mars.

Habitable Zones, Press Release, Titan, Water/Hycean Worlds & Oceanography

Air-sea Interactions On Titan: Effect Of Radiative Transfer On The Lake Evaporation And Atmospheric Circulation

by Keith CowingOctober 10, 2022October 10, 2022

Titan’s northern high latitudes host many large hydrocarbon lakes. Like water lakes on Earth, Titan’s lakes are constantly subject to evaporation.

ocean

Detectability Of Local Water Reservoirs In Europa’s Surface Layer Under Consideration Of Coupled Induction

Europa’s Coupled Ice-Ocean System: Temporal Evolution of a Pure Ice Shell

Circumpolar Ocean Stability On Mars 3 Billion Years Ago

The Distribution Of CO2 On Europa Indicates An Internal Source Of Carbon

The Spatial Distribution of the Unidentified 2.07 μm Absorption Feature on Europa and Implications for its Origin

Ocean Currents May Affect Rotation of Europa’s Icy Crust

How Enceladus Ejects Particles From Oceans Beneath Its Surface

Origin Of Water In The Terrestrial Planets: Insights From Meteorite Data And Planet Formation Models

Traces Of An Ancient Ocean Have Been Discovered On Mars

Air-sea Interactions On Titan: Effect Of Radiative Transfer On The Lake Evaporation And Atmospheric Circulation

Indigenizing The Drake Equation: How Indigenous Methods Can Help Us Understand Life In The Milky Way Galaxy

NASA Spaceline Current Awareness List #1,205 26 June 2026 (Space Life Science Research Results)

Theoretical and Experimental IR Spectra of Astronomical PAHs and PANHs in the 2000–1650 cm–1 Range (∼5–6 μm)

Ecological Constraints To Mirror Life

Theoretical Determination Of The Binding Energies Of Methanol And Related Species Onto Amorphous Solid Water Ice