Planetary magnetic field

Stevenson D. J. (2(X)3) Planetary magnetic fields. Earth Planet. Sci. Lett. 208, 1-11. 

Dynamo effect—A model for the generation of planetary magnetic fields The circulation of hot, conducting fluids within a planet s liquid core leads to the generation of a magnetic field. 

The Moon has no overall magnetic field. According to the currently favored model of planetary magnetic fields (the dynamo model), this means either that the Moon probably has no molten core or that only a very small part of the core is molten. There is a weak m net-ic field frozen into the rocks, however, or the rocks have a north pole and a south pole, so it s possible that the Moon cnce had a m nefic field surrounding it. 

Finally, studies of planets and their satelhtes show that internally generated magnetic fields do not require the existence of a metalUc core, particularly given the diverse nature of planetary magnetic fields in the solar system (Stevenson,... 

E. Planetary Magnetic Fields as Tests for Dynamo Mechanisms... 

Finally, we note that both synchrotron and cyclotron radiation from (solar system) planets is confined to the radio region of the spectrum. This circumstance is due to the range of planetary magnetic field strengths and particle energies found in the solar system. The existence of Jupiter s strong magnetic field was first deduced from earth-based measurements of its polarized radio emission. 

Non-thermal evaporation these processes are caused by the steUar wind and UV flux. If there is no strong planetary magnetic field, solar wind and EUV flux contribute to the escape of heavier particles. 

Magnetic Field. Its History, Origin, and Planetary Perspective. 1983... 

The latter half of the nineteenth century was a time of intellectual triumph in the physical sciences. Most of the material contained in the first year of modem college physics courses was completely understood by then. Newton s laws had been rephrased in different mathematical forms which simplified even complicated many-body problems such as planetary motion. In addition, the description of electric and magnetic fields by Maxwell s equations was an essentially complete success—so much so that these equations and their consequences are the central focus of some graduate physics courses even today. 

Volume 32 Ronald T. Merrill and Michael W. McElhinny. The Earth s Magnetic Field Its History, Origin and Planetary Perspective. 1983... 

Herndon, J. M. (2009). Nature of planetary matter and magnetic field generation in the solar system. Current Science, 96(8), 1033-1039. 

The absence of a strong field on Venus, despite its otherwise terrestrial bulk properties, is probably consistent with the dynamo mechanism. The planet rotates about a factor of 250 times more slowly than Earth. Mercury rotates slowly and is too small to support a strong convective core, but it does have a very detectable dipole moment of 2.4 X 10 G cm. Its field is very small, about 0.002 G, and is nearly aligned and probably a relic from the earlier stages of planetary evolution. Mars rotates with nearly the same period as Earth, but it is smaller and may only support a very small convective core. Mars has displayed vulcanic activity in the past, evidence for core or mantle convection, but the planet does not possess even a very weak intrinsic magnetic field. 

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