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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…
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…
Cosmic Ray and Solar Particle Investigations Over the South Polar Regions of the Sun
Sierks, H.; Kunow, H.; Muller-Mellin, R. +17 more
Observations of galactic cosmic radiation and anomalous component nuclei with charged particle sensors on the Ulysses spacecraft showed that heliospheric magnetic field structure over the south solar pole does not permit substantially more direct access to the local interstellar cosmic ray spectrum than is possible in the equatorial zone. Fluxes o…
Corotating Variations of Cosmic Rays Near the South Heliospheric Pole
Jokipii, J. R.; Kota, J.
Three-dimensional simulations of the heliospheric modulation of galactic cosmic ray protons show that corotating variations in the intensity can persist to quite high heliographic latitudes. Variations are seen at latitudes considerably higher than the maximum latitude extension of the heliographic current sheet, in regions where the solar wind ve…
Ulysses Above the Sun's South Pole: An Introduction
Smith, Edward J.; Marsden, Richard G.; Page, D. Edgar
Ulysses has explored the field and particle environment of the sun's polar region. The solar wind speed was fast and nearly constant above -50^circ latitude. Compositional differences were observed in slow (low-latitude) solar wind and in fast (high-latitude) solar wind. The radial magnetic field did not change with latitude, implying that polar c…
Observations of Energetic Particles with EPAC on Ulysses in Polar Latitudes of the Heliosphere
Franz, M.; Keppler, E.; Korth, A. +5 more
Measurements with the Energetic Particle Composition instrument (EPAC) aboard Ulysses show particles from near the ecliptic that were apparently accelerated by shocks associated with a corotating interaction region. The particles were detected together with the shocks and even when shocks no longer arrived at Ulysses up to -65^circ of heliographic…
Large-Scale Interplanetary Magnetic Field Configuration Revealed by Solar Radio Bursts
Stone, R. G.; Fainberg, J.; Reiner, M. J.
An instantaneous view of the interplanetary extension of the solar magnetic field is provided here by measurements from a space platform at high ecliptic latitudes of the trajectories of individual type III solar radio bursts. The Ulysses spacecraft provides this unique vantage point with an orbit taking it far from the ecliptic plane. The Ulysses…
Ulysses Radio and Plasma Wave Observations at High Southern Heliographic Latitudes
Goetz, K.; Kellogg, P. J.; MacDowall, R. J. +17 more
Ulysses spacecraft radio and plasma wave observations indicate that some variations in the intensity and occurrence rate of electric and magnetic wave events are functions of heliographic latitude, distance from the sun, and phase of the solar cycle. At high heliographic latitudes, solar type III radio emissions did not descend to the local plasma…
Over the Southern Solar Pole: Low-Energy Interplanetary Charged Particles
Simnett, G. M.; Pick, M.; Anderson, K. A. +11 more
The heliosphere instrument for spectrum, composition, and anisotropy (HISCALE) recorded the fluxes of low-energy ions and electrons (>50 kiloelectron volts) when Ulysses crossed the southern solar polar region and revealed that the large-scale structure of the heliosphere to at least ~-75^circ was significantly influenced by the near-equatorial…