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Origin of the Solar Wind From Composition Data
Geiss, J.; Gloeckler, G.; von Steiger, R.
The ESA/NASA spacecraft Ulysses is making, for the first time, direct measurements in the solar wind originating from virtually all places where the corona expands. Since the initial two polar passes of Ulysses occur during relatively quiet solar conditions, we discuss here the three main regimes of quasi-stationary solar wind flow: the high speed…
The Large-Scale Structure of the Heliospheric Current Sheet During the ULYSSES Epoch
Hoeksema, J. Todd
Ulysses is traversing the Sun's polar regions for the first time a year or two before solar minimum. If the heliospheric magnetic field behaves as we expect, the heliospheric current sheet (HCS) during this stage of the sunspot cycle should be quite stable and lie nearly flat, close to the equator. The high latitude solar fields should be unipolar…
Kinetic Properties of Heavy Ions in the Solar Wind From SWICS/Ulysses
Geiss, J.; Galvin, A. B.; Gloeckler, G. +1 more
The kinetic properties of heavy ions in the solar wind are known to behave in a well organized way under most solar wind flow conditions: Their speeds are all equal and faster than that of hydrogen by about the local Alfvén speed, and their kinetic temperatures are proportional to their mass. The simplicity of these properties points to a straight…
Interplanetary Shock Waves: ULYSSES Observations In and Out of the Ecliptic Plane
Balogh, A.; Forsyth, R. J.; Burton, M. E. +4 more
Between its launch in October 1990 and the end of 1993, approximately 160 fast collisionless shock waves were observed in the solar wind by the Ulysses space probe. During the in-ecliptic part of the mission, to February 1992, the observed shock waves were first caused mainly by solar transient events following the solar maximum and the reorganisa…
The flux of interstellar dust observed by ULYSSES and Galileo
Hamilton, D. P.; Grün, E.; Linkert, G. +4 more
Interstellar dust detected by the dust sensor onboard Ulysses was first identified after the Jupiter flyby when the spacecraft's trajectory changed dramatically (Grün et al., 1994). Here we report on two years of Ulysses post-Jupiter data covering the range of ecliptic latitudes from 0° to -54° and distances from 5.4 to 3.2 AU. We find that, over …
ULYSSES Observations of Latitude Gradients in the Heliospheric Magnetic Field: Radial Component and Variances
Balogh, A.; Tsurutani, B. T.; Smith, E. J. +3 more
The radial component of the magnetic field at Ulysses, over latitudes from -10° to -45° and distances from 5.3 to 3.8 AU, compares very well with corresponding measurements being made by IMP-8 in the ecliptic at 1AU. There is little, if any, evidence of a latitude gradient. Variances in the field, normalized to the square of the field magnitude, s…
Reverse Shock Acceleration of Electrons and Protons at Mid-Heliolatitudes From 5.3--3.8 AU
Simnett, G. M.; Roelof, E. C.
We examine the intensity, anisotropy and energy spectrum of 480 966 keV protons and 38 315 keV electrons observed by the HI-SCALE instrument on Ulysses associated with Corotating Interaction Regions (CIR) from mid-1992 to early 1994. The particle events are most clearly ordered by the reverse shocks bounding the CIRs. The bulk of the ion fluxes ap…
Magnetic Holes in the Solar Wind and Their Relation to Mirror Mode Structures
Balogh, A.; Tsurutani, B. T.; Smith, E. J. +4 more
Data obtained by the Ulysses magnetometer and solar wind analyzer have been combined to study the properties of magnetic holes in the solar wind between 1 and 5.4 AU and to 23° south latitude. Although the plasma surrounding the holes was generally stable against the mirror instability, there are indications that the holes may have been remnants o…
Solar Wind Corotating Stream Interaction Regions Out of the Ecliptic Plane: ULYSSES
McComas, D. J.; Goldstein, B. E.; Bame, S. J. +4 more
Ulysses plasma observations reveal that the forward shocks that commonly bound the leading edges of corotating interaction regions (CIRs) beyond ∼2 AU from the Sun at low heliographic latitudes nearly disappeared at a latitude of S26°. On the other hand, the reverse shocks that commonly bound the trailing edges of the CIRs were observed regularly …
Further Studies of Waves Accompanying the Solar Wind Pick-up of Interstellar Hydrogen
Balogh, A.; Tsurutani, B. T.; Smith, E. J. +2 more
Data collected by the magnetometer onboard the Ulysses spacecraft are surveyed for the occurrence of waves generated during the pick-up of interstellar hydrogen. Thirty one wave events were found during a 640 day study period, between March 21, 1992 and December 20, 1993 (after the Ulysses encounter with Jupiter). It is found that observation of t…