scholarly journals The Correlation between Rotational Gravity and Magnetic Field of Celestial Body

2021 ◽  
Vol 9 (5) ◽  
Author(s):  
Ying-Qiu Gu
Keyword(s):  
Magnetic Field ◽  
Celestial Body ◽  
Gravity And Magnetic

scholarly journals Geodesy, Geophysics and Fundamental Physics Investigations of the BepiColombo Mission

2021 ◽  
Vol 217 (2) ◽  
Author(s):  
Antonio Genova ◽  
Hauke Hussmann ◽  
Tim Van Hoolst ◽  
Daniel Heyner ◽  
Luciano Iess ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Surface Composition ◽  
Current Knowledge ◽  
Laser Altimeter ◽  
Fundamental Physics ◽  
Radio Science ◽  
Nasa Mission ◽  
Gravity And Magnetic ◽  
Working Groups ◽  
Science Investigations

AbstractIn preparation for the ESA/JAXA BepiColombo mission to Mercury, thematic working groups had been established for coordinating the activities within the BepiColombo Science Working Team in specific fields. Here we describe the scientific goals of the Geodesy and Geophysics Working Group (GGWG) that aims at addressing fundamental questions regarding Mercury’s internal structure and evolution. This multidisciplinary investigation will also test the gravity laws by using the planet Mercury as a proof mass. The instruments on the Mercury Planetary Orbiter (MPO), which are devoted to accomplishing the GGWG science objectives, include the BepiColombo Laser Altimeter (BELA), the Mercury orbiter radio science experiment (MORE), and the MPO magnetometer (MPO-MAG). The onboard Italian spring accelerometer (ISA) will greatly aid the orbit reconstruction needed by the gravity investigation and laser altimetry. We report the current knowledge on the geophysics, geodesy, and evolution of Mercury after the successful NASA mission MESSENGER and set the prospects for the BepiColombo science investigations based on the latest findings on Mercury’s interior. The MPO spacecraft of the BepiColombo mission will provide extremely accurate measurements of Mercury’s topography, gravity, and magnetic field, extending and improving MESSENGER data coverage, in particular in the southern hemisphere. Furthermore, the dual-spacecraft configuration of the BepiColombo mission with the Mio spacecraft at higher altitudes than the MPO spacecraft will be fundamental for decoupling the internal and external contributions of Mercury’s magnetic field. Thanks to the synergy between the geophysical instrument suite and to the complementary instruments dedicated to the investigations on Mercury’s surface, composition, and environment, the BepiColombo mission is poised to advance our understanding of the interior and evolution of the innermost planet of the solar system.

Controlled stimulation-burst targeted release by smart decentered core–shell microcapsules in gravity and magnetic field

Lab on a Chip ◽  
2014 ◽  
Vol 14 (23) ◽  
pp. 4451-4454 ◽  
Author(s):  
Xue-Hui Ge ◽  
Jin-Pei Huang ◽  
Jian-Hong Xu ◽  
Guang-Sheng Luo
Keyword(s):  
Magnetic Field ◽  
Core Shell ◽  
Gravity And Magnetic ◽  
Targeted Release

DIGITAL CONVOLUTION FOR COMPUTING GRAVITY AND MAGNETIC ANOMALIES DUE TO ARBITRARY BODIES

Geophysics ◽  
1975 ◽  
Vol 40 (6) ◽  
pp. 981-992 ◽  
Author(s):  
B. K. Bhattacharyya ◽  
M. E. Navolio
Keyword(s):  
Magnetic Field ◽  
Green’S Function ◽  
Green's Function ◽  
Magnetization Vector ◽  
Sampling Interval ◽  
Observation Point ◽  
Uniform Density ◽  
Gravity And Magnetic ◽  
Convolution Algorithm ◽  
Source Geometry

The magnetic and gravitational potentials and fields due to arbitrarily shaped bodies with homogeneous magnetization and uniform density distribution are expressed as a convolution of the source geometry and the Green’s function. The Green’s function depends on the location of the observation point and on either the magnetization vector (in the case of the magnetic field) or the density (in the case of the gravitational attraction). A fast digital convolution algorithm is used for efficiently and accurately calculating anomalies caused by irregular bodies. The shapes of the calculated anomalies faithfully reproduce the exact shapes when the sampling interval selected for digitizing the source geometry and the Green’s function is less than one‐tenth of the depth of the source. In the digital convolution method for computing anomalies, it is unnecessary, for any given structure, to perform analytical integration of the dipolar magnetic field or the gravitational field of a point mass. One of the examples given in the paper deals with the computation of the magnetic anomaly due to the irregularly shaped Round Butte Laccolith, Montana. The results are found to be in satisfactory agreement with the observed aeromagnetic data. A new method is also described for calculating the magnetization vector associated with the laccolith and the datum level of the magnetic observations.

Vibration Behavior of Gravity-Loaded Whirling Micro-Scale Shafts Influenced by an Axial Magnetic Field

2017 ◽  
Vol 17 (09) ◽  
pp. 1750110 ◽  
Author(s):  
K. B. Mustapha ◽  
Z. W. Zhong ◽  
S. B. A. Kashem
Keyword(s):  
Magnetic Field ◽  
High Speed ◽  
Axial Magnetic Field ◽  
Torsional Rigidity ◽  
Transformation Method ◽  
Theoretical Treatment ◽  
Micro Scale ◽  
Gravity And Magnetic ◽  
The Stability ◽  
Micro Vibration

Some high-speed rotating micro-machines and micro-vibration devices rely on the use of whirling micro-shafts subject to the effect of gravity and magnetic fields. At present, the consequences of the interaction between the elastic deformation of such shafts and the magnetic/gravitational field effects remain unresolved. Focusing on micro-scale whirling shafts with very high torsional rigidity, this study presents a theoretical treatment grounded in the theory of micro-continuum elasticity to examine the ramification of this interaction. The differential transformation method (DTM) is used to obtain extensive numerical results for qualitative assessments of the magnetic-gravitational effects interaction on standing, hanging and horizontally positioned spinning micro-scale shafts. The influence of bearing-support flexibility on the response of the whirling micro-shaft is also considered with rotational and translational springs. The gravitational sag reduces the stability of whirling standing micro-shafts and increases that of the hanging micro-shafts. Further, for all the micro-shafts configurations investigated, the magnetic field is observed to stiffen the response of the shaft and favorably shifts the critical points of vibration of the whirling shafts forward.

Potential fields and their partial derivatives produced by a 2D homogeneous polygonal source: A summary with some revisions

Geophysics ◽  
2011 ◽  
Vol 76 (4) ◽  
pp. L29-L34 ◽  
Author(s):  
Zhen Jia ◽  
Shiguo Wu
Keyword(s):  
Magnetic Field ◽  
Cross Section ◽  
Observation Point ◽  
Potential Fields ◽  
Data Sets ◽  
Partial Derivatives ◽  
First Order ◽  
Gravity And Magnetic ◽  
Derivatives Of ◽  
The Magnetic Field

We summarized and revised the present forward modeling methods for calculating the gravity- and magnetic-field components and their partial derivatives of a 2D homogeneous source with a polygonal cross section. The responses of interest include the gravity-field components and their first- and second-order partial derivatives and the magnetic-field components and their first-order partial derivatives. The revised formulas consist of several basic quantities that are common in all the formulations. A singularity appears when the observation point coincides with a polygon vertex. This singularity is removable for the gravity formulas but not for the others. The compact forms of the revised formulas make them easy to implement. We compare the gravity- and magnetic-field components and their partial derivatives produced by a 2D prism whose polygonal cross section approximates a cylinder with the corresponding analytical fields and partial derivatives of the cylinder. The perfect fittings presented by both data sets confirm the reliability of the updated formulas.

Sign in / Sign up

Export Citation Format

Share Document