Search Publications
Observed constraint on proton-proton relative velocities in the solar wind
Goldstein, Bruce E.; Neugebauer, Marcia; Gary, S. Peter +1 more
From June 1994 to December 1995 the Ulysses spacecraft was within 3 AU of the Sun and traveled from high southern to high northern heliospheric latitudes. For this period, SWOOPS instrument data obtained when the magnetic field was approximately aligned with the radial direction from the Sun have been analyzed. In the fast wind at high latitudes, …
Ulysses observations of the irregularly structured mid-latitude solar wind during the approach to solar maximum
McComas, D. J.; Gosling, J. T.; Skoug, R. M.
The Ulysses spacecraft reached 45°S heliolatitude in its second polar orbit on 5 February 2000. Solar wind observations over the first portion of Ulysses' second orbit have been remarkably different from those taken at mid-latitudes throughout its first orbit. During these portions of its first orbit, Ulysses crossed back and forth between the fas…
The latitudinal distribution of solar wind magnetic holes
Tsurutani, Bruce T.; Goldstein, Bruce E.; Neugebauer, Marcia +2 more
Using the fast latitude scan period of the Ulysses spacecraft, the occurrence of magnetic holes in the solar wind is investigated from -80° to +80° helio-latitude. Near the ecliptic, the large average value and the large variations of the hole count rate appear to be correlated with interaction regions. It is found, however, that at 30°north and s…
Slowdown of the Solar Wind in the Outer Heliosphere and the Interstellar Neutral Hydrogen Density
Wang, C.; Richardson, J. D.; Gosling, J. T.
Voyager 2 and Ulysses were at nearly the same latitude in the southern heliosphere at the beginning of 1999 and their radial separation was about 55 AU. The effect of pickup ions should be profound at Voyager's position, especially, the deceleration of the solar wind flow. This unique opportunity allows us to investigate the effect of pickup ions …
On the propagation of Jovian electrons in the heliosphere: Transport modelling in 4-D phase space
Fichtner, Horst; Potgieter, Marius; Ferreira, Stefan +1 more
For about 25 years the Jovian magnetosphere is known to be a strong source of electrons with energies up to ∼30 MeV. Many in-situ observations have not only confirmed this finding originally made with the Pioneer 10 spacecraft, but have also revealed that the Jovian electrons appear to be present, at least close to the ecliptic plane, in the dista…
Ulysses observations of the magnetic field structure within CIRs
Forsyth, R. J.; Dunlop, M. W.; Clack, D.
Ulysses encountered two separate sequences of corotating interaction regions (CIRs) in 1992-3 and 1996-7 when the spacecraft was in the southern and northern solar hemispheres, respectively. We have examined magnetometer data from one event observed in each hemisphere. Using two separate analytical methods we provide evidence for the magnetic fiel…
Long-term behavior of Jovian bKOM and nKOM radio emissions observed during the Ulysses-Jupiter encounter
Kaiser, M. L.; Desch, M. D.; Reiner, M. J.
We present observational evidence that the long-term behavior of Jovian bKOM and nKOM radio emissions observed during the Ulysses-Jupiter encounter was controlled by the sector structure of the solar wind. Specifically, we found brightenings in the Jovian bKOM emission, followed by a sudden cessation of the bKOM emission and an onset of an nKOM “e…
Fluctuations of the heliospheric magnetic field and the anisotropy of pickup ions
Balogh, A.; Erdős, G.; Németh, Z.
Pitch angle distribution of interstellar pickup ions at high heliographic latitude is studied. Based on high time resolution magnetic field observations by Ulysses during the south polar pass in 1994, we have determined the angular distribution of particles at the moment of ionization. Due to large deviations of the field from Parker's spiral, it …
Recurrence in MeV proton fluxes and anisotropies at 5 AU from the Sun
Balogh, A.; Dalla, S.
We report the observation of a recurrent pattern in proton fluxes and anisotropies at 5.2 AU from the Sun, made by the Anisotropy Telescopes on board the Ulysses spacecraft between April 1998 and May 1999, during the rising phase of solar cycle 23. The time delay between recurrent features of the pattern is not constant and increases from 122 to 1…