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The global heliospheric magnetic field polarity distribution as seen at Ulysses
Balogh, A.; Jones, G. H.
The Ulysses spacecraft is in a near-polar solar orbit with a period of 6.2 years. The heliospheric magnetic field polarity detected by Ulysses from its 1992 Jupiter encounter to the current time is presented, following ballistic mapping of the polarity information to the solar wind source surface, at approximately 2.5 solar radii. The spacecraft's…
Consequences of the Solar System passage through dense interstellar clouds
Fahr, H. J.; Yeghikyan, A. G.
Several consequences of the passage of the solar system through dense interstellar molecular clouds are discussed. These clouds, dense (more than 100 cm-3), cold (10-50 K) and extended (larger than 1 pc), are characterized by a gas-to-dust mass ratio of about 100, by a specific power grain size spectrum (grain radii usually cover the range 0.001-3…
Latitudinal and radial variation of >2 GeV/n protons and alpha-particles at solar maximum: Ulysses COSPIN/KET and neutron monitor network observations
Kunow, H.; Heber, B.; Müller-Mellin, R. +4 more
Ulysses, launched in October 1990, began its second out-of-ecliptic orbit in September 1997. In 2000/2001 the spacecraft passed from the south to the north polar regions of the Sun in the inner heliosphere. In contrast to the first rapid pole to pole passage in 1994/1995 close to solar minimum, Ulysses experiences now solar maximum conditions. The…
Mesoscale structure of a morning sector ionospheric shear flow region determined by conjugate Cluster II and MIRACLE ground-based observations
Janhunen, P.; Lester, M.; André, M. +10 more
We analyse a conjunction event of the Cluster II spacecraft with the MIRACLE ground-based instrument net-work in northern Fennoscandia on 6 February 2001, between 23:00 and 00:00 UT. Shortly after the spacecraft were located at perigee, the Cluster II satellites’ magnetic footpoints move northwards over Scandinavia and Svalbard, almost perfectly a…
The Ulysses fast latitude scans: COSPIN/KET results
Kunow, H.; Wibberenz, G.; Posner, A. +6 more
Ulysses, launched in October 1990, began its second out-of-ecliptic orbit in December 1997, and its second fast latitude scan in September 2000. In contrast to the first fast latitude scan in 1994/1995, during the second fast latitude scan solar activity was close to maximum. The solar magnetic field reversed its polarity around July 2000. While t…
Observation of energy-time dispersed ion structures in the magnetosheath by CLUSTER: possible signatures of transient acceleration processes at shock
Budnik, E.; Balogh, A.; Dandouras, I. +11 more
We analyse energy-time dispersed ion signatures that have been observed by CLUSTER in the dayside magnetosheath. These events are characterized by sudden increases in the ion flux at energies larger than 10 keV. The high energy ions (30 keV) are first detected, with the transition to the low energy ions (5 keV) lasting about 100 s. These injection…
Solar cycle variations of the energetic H/He intensity ratio at high heliolatitudes and in the ecliptic plane
Lario, D.; Roelof, E. C.; Maclennan, C. G. +3 more
We study the variability of the heliospheric energetic proton-to-helium abundance ratios during different phases of the solar cycle. We use energetic particle, solar wind, and magnetic field data from the Ulysses, ACE and IMP-8 spacecraft to compare the H/He intensity ratio at high heliographic latitudes and in the ecliptic plane. During the first…
From the Sun's south to the north pole - Ulysses COSPIN/LET composition measurements at solar maximum
Sanderson, T. R.; Marsden, R. G.; Tranquille, C. +1 more
Based on elemental abundance ratios derived from the Ulysses COSPIN/LET measurements, we classified the energetic particle populations during and after the socalled Fast Latitude Scan - the time period during which the Ulysses spacecraft traveled from the highest heliolatitude south to maximum northern latitude, i.e. 27 November 2000 to 13 October…
Latitudinal extent of large-scale structures in the solar wind
McComas, D. J.; Riley, P.; Elliott, H. A.
Comparison of solar wind observations from the ACE spacecraft, in the ecliptic plane at ~ 1 AU, and the Ulysses spacecraft as it orbits over the Sun's poles, provides valuable information about the latitudinal extent and variation of solar wind structures in the heliosphere. While qualitative comparisons can be made using average properties observ…
On the heliolatitudinal variation of the galactic cosmic-ray intensity. Comparison with Ulysses measurements
Moussas, X.; Exarhos, G.
We study the dependence of cosmic rays with heliolatitude using a simple method and compare the results with the actual data from Ulysses and IMP spacecraft. We reproduce the galactic cosmic-ray heliographic latitudinal intensity variations, applying a semi-empirical, 2-D diffusion-convection model for the cosmic-ray transport in the interplanetar…