Article
Geosciences, Multidisciplinary
Marc A. Hesse, Jacob S. Jordan, Steven D. Vance, Apurva Oza
Summary: Researchers have found that Jupiter's moon Europa has an ocean beneath its ice shell, and the habitability of this ocean depends on the availability of redox gradients. They propose that oxidants are transported through the ice shell by the drainage of near-surface brines, delivering 85% of the surface oxidants to the ocean.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Oceanography
Motoki Nagura, Michael J. Mcphaden
Summary: The frequency spectra of meridional velocity measurements in the central equatorial Indian Ocean show two distinct peaks at quasi biweekly periods. The variability in these two frequency bands represents wind-driven mixed Rossby-gravity waves, with different spatial structures. The results are consistent with linear mixed Rossby-gravity wave theory and surface wind forcing is the primary driver of these waves.
JOURNAL OF PHYSICAL OCEANOGRAPHY
(2023)
Article
Geosciences, Multidisciplinary
Mohit Melwani Daswani, Steven D. Vance, Matthew J. Mayne, Christopher R. Glein
Summary: Europa likely contains an iron-rich metal core, with temperatures reaching above 1250K. Volatiles released from the interior could have formed a carbonic ocean and early CO2 atmosphere without the need for late delivery of cometary water. Gypsum precipitation would create a 3-10 km thick sedimentary layer at the seafloor.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Astronomy & Astrophysics
S. M. Ressler, E. Quataert, C. J. White, O. Blaes
Summary: The 3D general relativistic magnetohydrodynamic simulations show that electromagnetic jets with outflow efficiencies can reach several hundred gravitational radii before dissipating. The direction of the jets fluctuates in time and can be tilted by as much as 30 degrees with respect to black hole spin. The simulations suggest that a tilted initial magnetic field can optimize the amount of magnetic flux reaching the black hole.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Geochemistry & Geophysics
E. M. Spiers, B. E. Schmidt
Summary: Europa's long-term habitability relies on thermodynamics, tidal evolution, and geochemical pathways, with hydrogen generated from water-rock reactions potentially serving as a metabolic energy source. The study illustrates how thermal changes to Europa's ice shell and ocean influence ocean salinity and serpentinization rates. Thermal-orbital evolution and oceanic salt content play crucial roles in the stability of serpentinization reactions on Europa, impacting hydrogen production rate significantly.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2023)
Article
Geosciences, Multidisciplinary
Kuiping Li, Yue Yin, Yang Yang, Yanliang Liu, Weidong Yu
Summary: This study investigates the dynamic response of the Wyrtki Jet (WJ), a dominant wind-driven surface current in the Indian Ocean, to the abrupt onset of the Bay of Bengal summer monsoon. The results indicate that the WJ tends to reach maximum strength around the monsoon onset, with a rapid acceleration before and a gradual deceleration after the onset. The study shows that the geostrophic term driven by equatorial westerlies plays a fundamental role in the evolution of the WJ. Before the monsoon onset, the burst of equatorial westerlies leads to rapid WJ acceleration, while the shift from westerlies to cross-equatorial flows during the monsoon onset results in the gradual reduction of the WJ in spring. The first-branch northward-propagating intraseasonal oscillation, which triggers both the burst of equatorial westerlies and the monsoon onset, is found to be an important factor in the relationship between the WJ and monsoon onset.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Review
Astronomy & Astrophysics
Steven D. Vance, Kathleen L. Craft, Everett Shock, Britney E. Schmidt, Jonathan Lunine, Kevin P. Hand, William B. Mckinnon, Elizabeth M. Spiers, Chase Chivers, Justin D. Lawrence, Natalie Wolfenbarger, Erin J. Leonard, Kirtland J. Robinson, Marshall J. Styczinski, Divya M. Persaud, Gregor Steinbrugge, Mikhail Y. Zolotov, Lynnae C. Quick, Jennifer E. C. Scully, Tracy M. Becker, Samuel M. Howell, Roger N. Clark, Andrew J. Dombard, Christopher R. Glein, Olivier Mousis, Mark A. Sephton, Julie Castillo-Rogez, Francis Nimmo, Alfred S. Mcewen, Murthy S. Gudipati, Insoo Jun, Xianzhe Jia, Frank Postberg, Krista M. Soderlund, Catherine M. Elder
Summary: The habitability of Europa is a complex property that requires collaborative investigation. The Europa Clipper mission aims to characterize the ice shell, ocean, composition, and geology of Europa, as well as explore potential activity and conduct reconnaissance for future missions. The mission's findings, combined with remote observations, will be used to assess Europa's habitability.
SPACE SCIENCE REVIEWS
(2023)
Review
Chemistry, Multidisciplinary
Huaijuan Zhou, Carmen C. Mayorga-Martinez, Salvador Pane, Li Zhang, Martin Pumera
Summary: Magnetic micro/nanorobots can be manipulated and guided in different fluid environments using magnetic fields, offering advantages such as remote control, reconfigurability, and fuel-free operation. They have diverse applications in targeted drug delivery, biofilm disruption, and environmental remediation.
Article
Geochemistry & Geophysics
C. J. Chivers, J. J. Buffo, B. E. Schmidt
Summary: Europa's ice shell conceals a global salty ocean that may support life, with geological cycles impacting conditions by allowing material transfer. Numerical models suggest that lenticulae may be more transient than previously thought, potentially indicating present-day formation of liquid water in Europa's shallow ice.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2021)
Article
Meteorology & Atmospheric Sciences
Yu Zhang, Shiyun Yu, Dillon J. Amaya, Yu Kosaka, Sarah M. Larson, Xudong Wang, Jun-Chao Yang, Malte F. Stuecker, Shang-Ping Xie, Arthur J. Miller, Xiaopei Lin
Summary: Investigating the North PMM and South PMM through a mechanically decoupled climate model simulation revealed new insights into their associated atmospheric forcing and response processes.
JOURNAL OF CLIMATE
(2021)
Article
Astronomy & Astrophysics
A. G. Marusiak, M. P. Panning, S. D. Vance, C. Nunn, S. C. Staehler, S. Tharimena
Summary: The study investigates the minimum magnitude of detectable seismic events originating from Europa's silicate interior and the sensitivity requirements for current instrumentation. Thinner ice shells allow for greater ground acceleration amplitudes, making seismic events easier to detect.
EARTH AND SPACE SCIENCE
(2022)
Article
Astronomy & Astrophysics
Ross R. Maguire, Nicholas C. Schmerr, Vedran Lekic, Terry A. Hurford, Lenore Dai, Alyssa R. Rhoden
Summary: Determining the thickness of Europa's outer ice shell is crucial for understanding its internal dynamics, evolution, and potential habitability. Seismic techniques could be used to probe Europa's interior structure and dynamics, including body wave, surface wave, and normal mode seismology. Results suggest that surface waves from naturally occurring ice fracturing events on Europa can help determine ice shell thickness.
Article
Oceanography
D. A. Cherian, D. B. Whitt, R. M. Holmes, R-C Lien, S. D. Bachman, W. G. Large
Summary: The study shows that deep-cycle turbulence occurs both on and off the equator in the cold tongue region, modulated by tropical instability waves. Further observational campaigns are needed to characterize the modulation of deep-cycle turbulence by TIWs both on and off the equator.
JOURNAL OF PHYSICAL OCEANOGRAPHY
(2021)
Article
Geosciences, Multidisciplinary
Finn Ole Heukamp, Peter Brandt, Marcus Dengler, Franz Philip Tuchen, Michael J. McPhaden, James N. Moum
Summary: Based on velocity data from a long-term moored observatory located at 0 degrees N, 23 degrees W, an asymmetry in northward and southward upper-ocean flow in the equatorial Atlantic Ocean during intraseasonal maxima is observed. The meridional velocity maximum close to the surface characterizes northward flow periods, while subsurface velocity maximum at about 40 m is observed during southward flow phases. The observed asymmetry is caused by the local winds, driving a wind-driven overturning cell known as the Equatorial Roll. The Equatorial Roll shows a distinct seasonal cycle linked to the south-easterly trade winds' meridional component.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geochemistry & Geophysics
N. S. Wolfenbarger, M. G. Fox-Powell, J. J. Buffo, K. M. Soderlund, D. D. Blankenship
Summary: This study presents a framework for modeling the distribution of brine in impure water ice, and explores the effects of temperature, bulk ice salinity, and brine composition on the stability and extent of brine within Europa's ice shell. The results highlight the importance of temperature and composition in determining the depth of stable brine within an ice shell.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Physics, Multidisciplinary
Christophe Gissinger
Article
Physics, Multidisciplinary
F. Petrelis, A. Alexakis, C. Gissinger
PHYSICAL REVIEW LETTERS
(2016)
Article
Mechanics
Paola Rodriguez Imazio, Christophe Gissinger
Article
Mechanics
Christophe Gissinger, Paola Rodriguez Imazio, Stephan Fauve
Article
Physics, Fluids & Plasmas
Florence Marcotte, Christophe Gissinger
PHYSICAL REVIEW FLUIDS
(2016)
Article
Physics, Fluids & Plasmas
A. Alexakis, S. Fauve, C. Gissinger, F. Petrelis
JOURNAL OF PLASMA PHYSICS
(2018)
Article
Physics, Fluids & Plasmas
K. Sandeep Reddy, Stephan Fauve, Christophe Gissinger
PHYSICAL REVIEW FLUIDS
(2018)
Article
Astronomy & Astrophysics
J. Philidet, C. Gissinger, F. Lignieres, L. Petitdemange
GEOPHYSICAL AND ASTROPHYSICAL FLUID DYNAMICS
(2020)
Article
Mechanics
M. Vernet, M. Pereira, S. Fauve, C. Gissinger
Summary: An experiment was conducted to study the flow of an electrically conducting fluid in a thin disc under the influence of an azimuthal Lorentz force. Different flow patterns were observed, including quasi-Keplerian velocity profiles, turbulent flow with large fluctuations and a Keplerian mean rotation profile, and a quasi-bidimensional turbulent flow with the formation of large scale condensates in the horizontal plane. These results are attributed to the instability of the Bodewadt-Hartmann layers at large Reynolds numbers and are discussed within the context of similar astrophysical turbulent flows.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Physics, Multidisciplinary
M. Vernet, S. Fauve, C. Gissinger
Summary: This laboratory study investigates the transport of angular momentum by turbulent flow in a thin disk of electrically conducting fluid. The experiment reveals that when a sufficiently large electromagnetic force is applied, the resulting turbulent flow exhibits a time-averaged Keplerian rotation rate characterized by r(-3/2). Two contributions to the local angular momentum transport are identified: one from poloidal recirculation induced by boundaries and the other from turbulent fluctuations in the bulk. The latter contribution leads to efficient angular momentum transport independent of fluid viscosity, consistent with Kraichnan's prediction.
PHYSICAL REVIEW LETTERS
(2022)
Article
Multidisciplinary Sciences
Ludovic Petitdemange, Florence Marcotte, Christophe Gissinger
Summary: The evolution of stars is influenced by internal rotation dynamics, but the mechanisms involved are not well understood. Magnetic fields may play a role in transporting angular momentum and chemical elements, but the origin of magnetism in radiative stellar layers is unclear. Through numerical simulations, we identified a subcritical transition from laminar flow to turbulence caused by a magnetic dynamo. This mechanism could produce strong magnetic fields inside radiative stars that are not observable on their surface.
Article
Physics, Fluids & Plasmas
Florence Marcotte, Basile Gallet, Francois Petrelis, Christophe Gissinger
Summary: Research shows that in systems with inhomogeneous electrical conductivity and magnetic permeability, the stability threshold of the Taylor-Couette kinematic dynamo can be significantly reduced when modulation is introduced. The extension of the duality argument suggests that swapping the distributions of conductivity and permeability and changing u -> -u does not alter the dynamo threshold.
Article
Physics, Multidisciplinary
M. Berhanu, E. Falcon, G. Michel, C. Gissinger, S. Fauve
Article
Physics, Fluids & Plasmas
M. Pereira, C. Gissinger, S. Fauve
