Characteristics of a plasma sheath in a magnetic dipole field: Implications to the solar wind interaction with the lunar magnetic anomalies

2012 ◽  
Vol 117 (A6) ◽  
pp. n/a-n/a ◽  
Author(s):  
X. Wang ◽  
M. Horányi ◽  
S. Robertson
Keyword(s):  
Solar Wind ◽  
Magnetic Dipole ◽  
Magnetic Anomalies ◽  
Plasma Sheath ◽  
Dipole Field ◽  
Solar Wind Interaction ◽  
Magnetic Dipole Field

scholarly journals Calibration of Radiocarbon Dates for the Late Pleistocene Using U/Th Dates on Stalagmites

Radiocarbon ◽  
1997 ◽  
Vol 39 (1) ◽  
pp. 27-32 ◽  
Author(s):  
John C. Vogel ◽  
Joel Kronfeld
Keyword(s):  
South Africa ◽  
Magnetic Dipole ◽  
Satisfactory Agreement ◽  
Late Pleistocene ◽  
Calibration Curve ◽  
Dipole Field ◽  
Radiocarbon Dates ◽  
The Past ◽  
The Earth ◽  
Magnetic Dipole Field

Twenty paired 14C and U/Th dates covering most of the past 50,000 yr have been obtained on a stalagmite from the Cango Caves in South Africa as well as some additional age-pairs on two stalagmites from Tasmania that partially fill a gap between 7 ka and 17 ka ago. After allowance is made for the initial apparent 14C ages, the age-pairs between 7 ka and 20 ka show satisfactory agreement with the coral data of Bard et al. (1990, 1993). The results for the Cango stalagmite between 25 ka and 50 ka show the 14C dates to be substantially younger than the U/Th dates except at 49 ka and 29 ka, where near correspondence occurs. The discrepancies may be explained by variations in 14C production caused by changes in the magnetic dipole field of the Earth. A tentative calibration curve for this period is offered.

Solar Wind and Terrestrial Planets

2020 ◽  
Author(s):  
Edik Dubinin ◽  
Janet G. Luhmann ◽  
James A. Slavin
Keyword(s):  
Magnetic Field ◽  
Solar Wind ◽  
Electric Fields ◽  
Interplanetary Space ◽  
Upper Atmosphere ◽  
Dipole Field ◽  
Terrestrial Planets ◽  
Solar Wind Interaction ◽  
Additional Energy ◽  
First Case

Knowledge about the solar wind interactions of Venus, Mars, and Mercury is rapidly expanding. While the Earth is also a terrestrial planet, it has been studied much more extensively and in far greater detail than its companions. As a result we direct the reader to specific references on that subject for obtaining an accurate comparative picture. Due to the strength of the Earth’s intrinsic dipole field, a relatively large volume is carved out in interplanetary space around the planet and its atmosphere. This “magnetosphere” is regarded as a shield from external effects, but in actuality much energy and momentum are channeled into it, especially at high latitudes, where the frequent interconnection between the Earth’s magnetic field and the interplanetary field allows some access by solar wind particles and electric fields to the upper atmosphere and ionosphere. Moreover, reconnection between oppositely directed magnetic fields occurs in Earth’s extended magnetotail—producing a host of other phenomena including injection of a ring current of energized internal plasma from the magnetotail into the inner magnetosphere—creating magnetic storms and enhancements in auroral activity and related ionospheric outflows. There are also permanent, though variable, trapped radiation belts that strengthen and decay with the rest of magnetospheric activity—depositing additional energy into the upper atmosphere over a wider latitude range. Virtually every aspect of the Earth’s solar wind interaction, highly tied to its strong intrinsic dipole field, has its own dedicated textbook chapters and review papers. Although Mercury, Venus, Earth, and Mars belong to the same class of rocky terrestrial planets, their interaction with solar wind is very different. Earth and Mercury have the intrinsic, mainly dipole magnetic field, which protects them from direct exposure by solar wind. In contrast, Venus and Mars have no such shield and solar wind directly impacts their atmospheres/ionospheres. In the first case, intrinsic magnetospheric cavities with a long tail are found. In the second case, magnetospheres are also formed but are generated by the electric currents induced in the conductive ionospheres. The interaction of solar wind with terrestrial planets also varies due to changes caused by different distances to the Sun and large variations in solar irradiance and solar wind parameters. Other important planetary differences like local strong crustal magnetization on Mars and almost total absence of the ionosphere on Mercury create new essential features to the interaction pattern. Solar wind might be also a feasible driver for planetary atmospheric losses of volatiles, which could historically affect the habitability of the terrestrial planets.

Kinematic Model of a Magnetic-Microrobot Swarm in a Rotating Magnetic Dipole Field

2020 ◽  
Vol 5 (2) ◽  
pp. 2419-2426 ◽  
Author(s):  
BhanuKiran Chaluvadi ◽  
Kristen M. Stewart ◽  
Adam J. Sperry ◽  
Henry C. Fu ◽  
Jake J. Abbott
Keyword(s):  
Magnetic Dipole ◽  
Kinematic Model ◽  
Dipole Field ◽  
Magnetic Dipole Field

Periodic orbits of an electric charge in a magnetic dipole field

1991 ◽  
Vol 49 (4) ◽  
pp. 327-345 ◽  
Author(s):  
Lidia Jim�nez-Lara ◽  
Eduardo Pi�a
Keyword(s):  
Periodic Orbits ◽  
Magnetic Dipole ◽  
Electric Charge ◽  
Dipole Field ◽  
Magnetic Dipole Field

Photoproduction of gravitons in a static magnetic dipole field due to currents

1978 ◽  
Vol 56 (6) ◽  
pp. 801-805 ◽  
Author(s):  
G. Papini ◽  
S. R. Valluri
Keyword(s):  
Gravitational Field ◽  
Magnetic Dipole ◽  
Cross Section ◽  
Dipole Field ◽  
Radiative Corrections ◽  
Gauge Invariant ◽  
Magnetic Dipole Field ◽  
The Cross

The cross section for the photoproduction of gravitons in magnetic dipole fields which are due to steady currents is calculated. The approach and the results are compared with the previously studied case in which no currents exist and the potential is represented by a scalar. The calculations in both cases are completely covariant and electromagnetically gauge invariant. The radiative corrections to order [Formula: see text] and [Formula: see text] in the nonrelativistic and relativistic limits are also calculated for dipole and Coulomb fields, respectively. Their evaluation is particularly simple in the transverse traceless gauge for the gravitational field.

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