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Ulysses observations from pole-to-pole: An introduction
Smith, Edward J.; Marsden, Richard G.
Recent results from the Ulysses spacecraft as it observed particles and fields above the Sun's south polar cap, returned rapidly across the equator and traversed the northern solar hemisphere are presented in subsequent articles. This introduction provides a brief description of the spacecraft, the experiments, the unique trajectory and highlights…
Ulysses observations of opposed tilts of solar wind corotating interaction regions in the northern and southern solar hemispheres
McComas, D. J.; Forsyth, R. J.; Phillips, J. L. +3 more
Data obtained during Ulysses' rapid northbound traverse across the heliographic equator provide evidence for predicted, opposed north-south tilts of corotating interaction regions formed from streams originating in the northern and southern solar hemispheres respectively. In both hemispheres, reverse waves that were propagating poleward were obser…
The Ulysses south polar pass: Transient fluxes of energetic ions
Balogh, A.; Forsyth, R. J.; Goldstein, B. E. +5 more
Using Ulysses low energy telescope (LET) measurements of protons and alpha particles with energies of ∼1-5 MeV/n, we present first observations of transient energetic particle events in the high latitude heliosphere. Three transient particle events with gradual onsets and time durations of several days have been identified in the LET data at helio…
The low radio frequency limit of solar type III bursts: Ulysses observations in and out of the ecliptic
Hoang, S.; Leblanc, Y.; Dulk, G. A.
We measure the low frequency limit flo of 1028 type III bursts and compare it with the observed plasma frequency at the spacecraft fp. We consider three periods: when Ulysses was in the ecliptic plane near the Sun, far from the Sun, and out of the ecliptic; the average plasma frequency was 20, 10, and 5 kHz respectively. The …
Abundances of ammonia and carbon disulfide in the Jovian stratosphere following the impact of comet Shoemaker-Levy 9
Edgington, S. G.; Atreya, S. K.; Trafton, L. M. +3 more
Radiative transfer-scattering models were used to fit the Hubble Space Telescope UV spectroscopic observations of Jupiter taken 2.5 hours after the impact of fragment G of comet P/Shoemaker-Levy 9. They yield abundances for NH3 and CS2 of (0.25-1.3) × 1016cm-2 and (0.43-1.1) × 1015cm-2
An intercomparison of plasma turbulence at three comets: Grigg-Skjellerup, Giacobini-Zinner, and Halley
Glassmeier, K. -H.; Neubauer, F. M.; Tsurutani, Bruce T.
We examine and intercompare the LF plasma wave turbulence at three comets: Grigg-Skjellerup (GS), Giacobini-Zinner (GZ), and Halley (H). All three have power spectral peaks at the local ion cyclotron frequency (the pump wave) at ∼10-2 Hz, and a power-law fall-off at higher frequencies that suggest the development of turbulent cascades […
Latitudinal structure of a coronal mass ejection inferred from Ulysses and Geotail observations
Balogh, A.; Phillips, J. L.; Gosling, J. T. +7 more
We present the first observations of a CME by two spacecraft separated substantially in heliographic latitude. Ulysses and Geotail both see similar features in the plasma and magnetic field parameters during an interval in which Geotail is located in the deep magnetosheath (>150 RE) and Ulysses is located in the solar wind at 5 AU, ∼…
Constraints on Solar Wind Acceleration Mechanisms from ULYSSES Plasma Observations: The First Polar Pass
Phillips, John L.; Barnes, Aaron; Gazis, Paul R.
The mass flux density and velocity of the solar wind at polar latitudes can provide strong constraints on solar wind acceleration mechanisms. We use plasma observations from the first polar passage of the Ulysses spacecraft to investigate this question. We find that the mass flux density and velocity are too high to reconcile with acceleration of …
Differences between the 0.35-1.0 MeV/nucleon H/He ratio in solar and Co-rotating events at high heliolatitude
Simnett, G. M.; Roelof, E. C.; Sayle, K. A.
We discuss measurements from the Ulysses spacecraft of the 0.35-1.0 MeV/nucleon H/He intensity ratio at high heliolatitudes. In early 1994 two transient solar events were detected in the gaps between particle intensity increases associated with the passage at low latitude of a co-rotating interaction region. The H/He ratio was ≳ one order-of-magni…
Tangential discontinuities at high heliographic latitudes (∼-80°)
Balogh, A.; Tsurutani, B. T.; Goldstein, B. E. +2 more
In this study, tangential discontinuities (TDs) near -80° heliographic latitude have been studied. Based on our quantitative definitions, we find that the TDs may generally be divided into two clear types. There is a distinct population of TDs small (<40°) directional changes. About 19% of all high-latitude TDs are in this category. These types…