Results 221 to 230 of about 7,493,826 (258)

Harnessing legal structures of virtue for planetary health

Journal of Medical Ethics, 2023
Humans and other species depend on the planet’s well-being to survive and flourish. The health of the planet and its ecosystems is under threat from anthropogenic climate change, pollution and biodiversity loss. The promotion of planetary health against entrenched degradation of nature urgently requires ethical guidance.
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Peripheral Structures of Planetary Systems

Solar System Research, 2004
We analyze the conditions for the formation and time evolution of peripheral comet structures of solar-type planetary systems. In the Solar system, these include the Kuiper belt, the Oort cloud, the comet spear, and the Galactic comet ring that marks the Galactic orbit of the Sun. We consider the role of the viscosity of a protoplanetary gas–dust disk,
A. V. Tutukov, M. A. Smirnov
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The Fine Structures of Planetary Nebulae

Astrophysics and Space Science, 2000
Most theoretical studies of the dynamics of planetary nebulae assume that the slow ejecta from the red-giant or asymptotic giant branch phase of evolution of the central star is distributed smoothly. We consider briefly the observational evidence for small scale structure in both neutral and ionised PNe gas, examine some of the ways it can be generated
J.E. Dyson, T.W. Hartquist, M.P. Redman, R.J.R. Williams   +3 more
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Planetary structures in general relativity

pure and applied geophysics, 1972
For a static single-zone planet assuming that 1) the pressure and density are connected by the equationP =K Q 1+1/n–s, 2) a complete spherical symmetry is preserved and the system is in hydrostatic equilibrium; in section II, the expressions for the field equations have been obtained in suitable dimensionless forms.
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Anisotropy and Coherent Vortex Structures in Planetary Turbulence

Science, 1994
High-resolution numerical simulations were made of unforced, planetary-scale fluid dynamics. In particular, the simulation was based on the quasi-geostrophic equations for a Boussinesq fluid in a uniformly rotating and stably stratified environment, which is an idealization for large regions of either the atmosphere or ocean.
J C, McWilliams, J B, Weiss, I, Yavneh
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Modeling of the planetary structure of the ionosphere and the protonosphere coupling

pure and applied geophysics, 1988
A planetary model of the ionosphere and the protonosphere coupling is described. The system of three-dimensional nonstationary modeling equations of continuity and motion for the ions O+ and H+ is presented. Some numerical results of model calculations are compared with the experimental data.
Yu. S. Saenko, N. S. Natsvalyan, N. Yu. Tepenitsyna   +2 more
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The internal structure of planetary bodies

Contemporary Physics, 1972
Abstract Each planet in the Solar System is represented as a mechanically spherical cold body, possibly in rotation. It is seen that, on this basis, the properties of the planets can be understood within the already established principles of the physics of matter under high pressures.
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Structural and spectroscopic characterization of mixed planetary ices

Faraday Discussions, 2010
Mixed ices play a central role in characterizing the origin, evolution, stability and chemistry of planetary ice surfaces. Examples include the polar areas of Mars, the crust of the Jupiter moon Europa, or atmospheres of planets and their satellites, particularly in the outer solar system.
Plattner, N., Lee, M. W., Meuwly, M.
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The Composition and Structure of Planetary Rings

1985
The properties of planetary ring systems are summarized herein; emphasis is given to the available evidence on their compositions and to their dynamical attributes. Somewhat contaminated water ice makes up the vast expanse of Saturn’s rings. Modified methane ice may comprise Uranus’ rings while silicates are the likely material of the Jovian ring ...
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Structures in Planetary Rings— Stability and Gravitational Scattering

2007
Two alternative theoretical approaches for the explanation of the irregular structure in the A and B ring of Saturn are presented: An oscillatory viscous instability and a model for gravitational scattering of the ring-matter at large (> 100m) ring-boulders.
Spahn, Frank (Prof. Dr.), Schmidt, Jürgen (Prof. Dr.), Sremcevic, Miodrag   +2 more
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