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Mihalov, J. D.

Publications and source records attributed to Mihalov, J. D..

At least 91 records · Page 5
All sourcesNASA NTRSDOE OSTI
NASA NTRS1972

Average plasma-sheet configuration near 60 earth radii.

Nearly three years of Ames magnetometer data from Explorer 35 are used to establish plasma-sheet configurations in the geomagnetic tail at the lunar orbit. The plasma sheet is defined either as a region with different field orientations from normal magnetic-field directions in the tail, or as a region where the magnetic field variance is greater than elsewhere in the tail. The plasma-sheet configuration at the lunar orbit derived in this manner is found to be similar to the distribution at 18 earth radii observed by Vela satellites. The seasonal dependence and variations with geomagnetic activity are also presented.

Meng, C.-I.↗
NASA NTRS1972

Lunar fossil magnetism and perturbations of the solar wind.

Perturbations of the solar wind downstream of the moon and lying outside of the rarefaction wave that defines the diamagnetic cavity are used to define possible source regions comprised of intrinsically magnetized areas of the moon. A map of the moon is constructed showing that a model in which the sources are exposed to the grazing solar wind during the lunation yields a selenographically invariant set of regions strongly favoring the lunar highlands over the maria. An alternative model with the source due to electromagnetic induction is explored. The ages of the field sources should be consistent with those based on the basalt ages and possibly far older if the sources are connected with the formation of the highland rocks themselves. The perturbations are tentatively identified as weak shock waves, and a Mach angle in accord with nominal values for the solar wind is found.

Sonett, C. P.↗
NASA NTRS1971

Average solar wind proton properties from Pioneers 6 and 7.

Distributions and average values for the proton speed, azimuthal and polar flow directions, and the proton temperature and density in the solar wind are presented. The data are obtained from the Ames plasma probes on Pioneers 6 and 7. The time periods covered include Dec. 18, 1965 to mid-February 1966, and mid-August to mid-October 1966. The distributions of the parameters, except for the polar flow direction, are skewed, partially because of stream-stream interactions in the solar wind. The average values of the basic plasma parameters from the two spacecraft are different which could be due partially to different solar activity at the two times, and partially to sector and beam structure dependence.

Mihalov, J. D.↗
NASA NTRS1971

Induced and permanent magnetism on the moon - Structural and evolutionary implications.

It is shown that the moon possesses an extraordinary response to induction from the solar wind due to a combination of a high interior electrical conductivity together with a relatively resistive crustal layer into which the solar wind dynamic pressure forces back the induced field. The dark side response, devoid of solar wind pressure, is approximately that expected for the vacuum case. These data permit an assessment of the interior conductivity and an estimate of the thermal gradient in the crustal region. The discovery of a large permanent magnetic field at the Apollo 12 site corresponds approximately to the paleomagnetic residues discovered in both Apollo 11 and 12 rock samples. The implications regarding an early lunar magnetic field are discussed and it is shown that among the various conjectures regarding the early field the most prominent are either an interior dynamo or an early approach to the earth though no extant model is free of difficulties.

Sonett, C. P.↗
NASA NTRS1970

Pressure balance across the distant magnetopause

Pressure conditions across distant magnetopause from interplanetary magnetic field measurements, comparing Pioneer 7 plasma data with Explorer 33 distant geomagnetic tail field magnitudes

Feldman, W. C.↗