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Ulysses solar wind plasma observations from pole to pole
McComas, D. J.; Goldstein, B. E.; Bame, S. J. +8 more
We present Ulysses solar wind plasma data from the peak southerly latitude of -80.2° on 12 September 1994 through the corresponding northerly latitude on 31 July 1995. Ulysses encountered fast wind throughout this time except for a 43° band centered on the solar equator. Median mass flux was nearly constant with latitude, while speed and density h…
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 Heliospheric Magnetic Field Over the South Polar Region of the Sun
Balogh, A.; Tsurutani, B. T.; Horbury, T. S. +3 more
Magnetic field measurements from the Ulysses space mission over the south polar regions of the sun showed that the structure and properties of the three-dimensional heliosphere were determined by the fast solar wind flow and magnetic fields from the large coronal holes in the polar regions of the sun. This conclusion applies at the current, minimu…
Three-dimensional magnetic reconnection and the magnetic topology of coronal mass ejection events
Hesse, M.; Gosling, J. T.; Birn, J.
Measurements of suprathermal electron fluxes in the solar wind indicate that field lines within coronal mass ejections, CMEs, near and beyond 1 AU are normally connected to the Sun at both ends. However, on occasion some field lines embedded deep within CMEs appear to be connected to the Sun at only one end. Here we propose an explanation for how …
The Southern High-Speed Stream: Results from the SWICS Instrument on Ulysses
Livi, S.; Balsiger, H.; Geiss, J. +8 more
The high-speed solar wind streaming from the southern coronal hole was remarkably uniform and steady and was confined by a sharp boundary that extended to the corona and chromosphere. Charge state measurements indicate that the electron temperature in this coronal hole reached a maximum of about 1.5 million kelvin within 3 solar radii of the sun. …
Ulysses Solar Wind Plasma Observations at High Southerly Latitudes
McComas, D. J.; Goldstein, B. E.; Bame, S. J. +7 more
Solar wind plasma observations made by the Ulysses spacecraft through -80.2^circ solar latitude and continuing equatorward to -40.1^circ are summarized. Recurrent high-speed streams and corotating interaction regions dominated at middle latitudes. The speed of the solar wind was typically 700 to 800 kilometers per second poleward of -35^circ. Coro…
Ulysses observations of the radial magnetic field
Balogh, A.; Smith, Edward J.
The radial component of the magnetic field in the southern hemisphere has been measured at Ulysses as it traveled from the equator to -80.2° latitude and returned. The radial component multiplied by the square of the radial distance, i.e., BRr2, averaged over 77 day intervals (three solar rotations) is approximately constant …
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…
Ulysses observations of Alfvén waves in the southern and northern solar hemispheres
Balogh, A.; Smith, E. J.; Neugebauer, M. +1 more
Alfvén waves with periods from <1 to >10 hours are shown to be continuously present in the sun's south and north polar regions. Below ≈ 30° latitude, as revealed by the rapid traversal of the equatorial region by Ulysses, the wave power averaged over a solar rotation decreases abruptly. The correlations between magnetic field and solar wind …
Properties of magnetohydrodynamic turbulence in the solar wind as observed by Ulysses at high heliographic latitudes
Balogh, A.; Horbury, T. S.; Smith, E. J. +3 more
The Ulysses mission provides an opportunity to study the evolution of magnetohydrodynamic (MHD) turbulence in pure high-speed solar wind streams. The absence at high heliocentric latitudes of the strong shears in solar wind velocity generally present near the heliocentric current sheet allows investigation of how fluctuations in the magnetic field…