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Neugebauer, M.

Publications and source records attributed to Neugebauer, M..

At least 217 records · Page 12
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Interaction effects between solar wind and comet Bennett

Observations of the solar wind and the comet Bennett made during the period from Mar. 23 to Apr. 5, 1970 are considered. During this period the position of the comet had been comparatively close to earth at a distance of about 0.7 AU. Plasma data from four space probes and photographs of a number of observatories are taken into account. The relation between a sudden change in the velocity of the solar wind and the occurrence of a pronounced disturbance in the cometary tail is investigated.

Burlaga, L. F.↗
NASA NTRS1972

Solar wind interaction with Comet Bennett (1969i

The relations are examined between the solar-wind and Comet Bennett during the period 23 March to 5 April 1970. A large kink was observed in the ion tail of the comet on April 4, but no solar wind stream was observed in the ecliptic plane which could have caused the kink. Thus, either there was no correlation between the solar wind at the earth and that at Comet Bennett (which was 40 deg above the ecliptic) or the kink was caused by something other than a high-speed stream. The fine structure visible in photographs of the kink favors the second of these alternatives. It is shown that a shock probably passed through Comet Bennett on March 31, but no effect was seen in photographs of the comet. A stream preceded by another shock and a large abrupt change in momentum flux might have intercepted the comet between 24 March and 28 March, but again no effect was seen in photographs of the Comet. In view of these results, the possibility must be considered that a large, abrupt change in momentum flux of the solar-wind is neither necessary nor sufficient to cause a large kink in a comet tail.

Burlaga, L. F.↗
NASA NTRS1972

Twenty-seven-day recurrences in the solar-wind speed - Mariner 2.

Results of an autocorrelation analysis of the Mariner 2 data concerning solar-wind speed obtained in late 1962. A statistically significant correlation associated with the solar rotation has been found near a lag of 27 days; however, the amplitude of the correlation is only about 0.4, in essential agreement with measurements of Vela 2 and 3 during the period from July 1964 to July 1967. The relatively modest correlation is interpreted to mean that a number of speed structures observed by Mariner 2 did not endure for more than one solar rotation; those structures that did endure evolved significantly in shape, amplitude, and solar longitude from one solar rotation to the next. The analysis also shows that typical solar-wind structures occupied about 30 to 45 deg in solar longitude near 1 AU.

Gosling, J. T.↗
NASA NTRS1972

Dissipation mechanisms in a pair of solar-wind discontinuities.

A pair of sharp closely spaced discontinuities in the solar wind was recorded by the high time resolution instruments aboard Ogo 5 on Mar. 14, 1968. There is plasma turbulence within the double structure, and there appear to be small-amplitude hydromagnetic waves radiating from the discontinuities. The generation of the plasma turbulence is discussed in terms of magnetic drift waves. Although it seems probable that the surfaces are tangential discontinuities, arguments are also advanced that the double structure may represent the Petschek mechanism in which rapid field-line merging occurs between standing waves.

Unti, T. W. J.↗
NASA NTRS1972

Solar wind spectrometer experiment

With the deployment of the Apollo 15 lunar surface experiments package, two identical solar-wind spectrometers (SWS), separated by approximately 1100 km, are now on the lunar surface. The spectrometers provide the first opportunity to measure the properties of the solar plasma simultaneously at two locations a fixed distance apart. It is hoped that these simultaneous observations will yield new information about the plasma and its interaction with the Moon and the geomagnetic field. At the time of preparation of this report, magnetic tapes of only 20 hours of simultaneous data had been received. These data are discussed.

Clay, D. R.↗
NASA NTRS1971

Computation of solar wind parameters from the OGO-5 plasma spectrometer data using Hermite polynomials

The method used to calculate the velocity, temperature, and density of the solar wind plasma is presented from spectra obtained by attitude-stabilized plasma detectors on the earth satellite OGO 5. The method, which used expansions in terms of Hermite polynomials, is very inexpensive to implement on an electronic computer compared to the least-squares and other iterative methods often used for similar problems.

Neugebauer, M.↗
NASA NTRS1968

Alfven waves in the solar wind.

Mariner 2 interplanetary plasma and magnetic field measurements for hydromagnetic waves /Alfven waves/ in solar wind

Neugebauer, M.↗