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Ulysses observations of a recurrent high speed solar wind stream and the heliomagnetic streamer belt
McComas, D. J.; Goldstein, B. E.; Bame, S. J. +4 more
Near-ecliptic solar wind observations by Ulysses on its way to the polar regions of the Sun, compared with those from IMP 8 at 1 AU, showed that high-speed streams decay and broaden with heliocentric distance from IMP 8 to Ulysses, as expected. In July 1992 while travelling south at ∼13°S and 5.3 AU, Ulysses encountered a recurrent high-speed stre…
Perpendicular transport in 1- and 2-dimensional shock simulations
Giacalone, J.; Jokipii, J. R.; Kota, J.
We consider the foundations of 1- and 2-dimensional shock simulations in which the physical quantities are independent of a coordinate which is not parallel to the magnetic field. We show analytically that in such simulations the ions are effectively tied to the convected magnetic lines of force because of the presence of an ignorable spatial coor…
Latitudinal variation of solar wind corotating stream interaction regions: Ulysses
McComas, D. J.; Goldstein, B. E.; Bame, S. J. +4 more
Ulysses’ initial transit to high heliographic latitudes at a heliocentric distance of ∼5 AU has revealed systematic effects in the latitudinal evolution of corotating interaction regions (CIRs). At a latitude corresponding roughly to, but slightly less than, the inferred tilt of the coronal streamer belt and embedded heliospheric current sheet, th…
Disappearance of the heliospheric sector structure at Ulysses
Balogh, A.; Tsurutani, B. T.; Forsyth, R. J. +6 more
In May, 1993, the heliospheric current sheet (HCS) ceased to be seen by the Ulysses spacecraft at a heliocentric latitude of ∼30° S and distance of 4.7 AU. The disappearance of the HCS coincided with the solar wind speed remaining >560 km/s and with the disappearance of one of four interaction regions previously seen on each solar rotation. The…
Counterstreaming suprathermal electron events upstream of corotating shocks in the solar wind beyond ∼2 Au: Ulysses
McComas, D. J.; Goldstein, B. E.; Bame, S. J. +3 more
Enhanced fluxes of suprathermal electrons are commonly observed upstream of corotating forward and reverse shocks in the solar wind at heliocentric distances beyond ∼2 AU by the Los Alamos plasma experiment on Ulysses. The average duration of these events, which are most intense immediately upstream from the shocks and which fade with increasing d…
Discrete wave packets at the proton cyclotron frequency at comet P/Halley
Neubauer, F. M.; Mazelle, C.
We present in this letter the first experimental evidence for wave packets near the local proton cyclotron frequency in the plasma environment of a comet. The observations have been made by the GIOTTO magnetometer experiment (MAG) around comet P/Halley on both sides of closest approach. The waves are always left-handed in the spacecraft frame, ell…
The evolution of the interplanetary sector structure in 1992
Balogh, A.; Forsyth, R. J.; Smith, E. J. +1 more
The unique vantage point of the Ulysses spacecraft throughout 1992 and the beginning of 1993, at a close to constant heliocentric distance of about 5 AU and a slowly varying heliographic latitude from 5° to 30° south is used to describe and discuss the evolution of the sector structure of the interplanetary magnetic field during the declining phas…
Pickup water group ions at comet Grigg-Skjellerup
Coates, A. J.; Winningham, J. D.; Borg, H. +9 more
The density and velocity distribution of cometary water group ions was measured by the Giotto spacecraft in the regions upstream and downstream of the ‘bow shock’ at comet Grigg-Skjellerup. The results show that the distributions of ions are ring-like until quite close to the shock, the timescales for pitch angle and energy diffusion appear simila…
Prediction of the heliospheric current sheet tilt: 1992 - 1996
Hoeksema, J. T.; McComas, D. J.; Suess, S. T.
Heliospheric current sheet tilt evolves systematically over the solar cycle. Here we show that this evolution is different than the sunspot cycle and that tilt for the period 1992 - 1996 can be predicted using persistence. That is, the tilt over the coming cycle will be the same as for the past cycle. The Ulysses spacecraft has passed Jupiter and …
Source characteristics and locations of hectometric radio emissions from the northern Jovian hemisphere
Stone, R. G.; Fainberg, J.; Reiner, M. J.
Northern Jovian hectometric (HOM) radio emissions, detected from high Jovian latitudes by the Unified Radio and Plasma Wave (URAP) experiment on the Ulysses spacecraft, were observed at all Jovian longitudes. This emission was observed to be predominantly right-hand circularly polarized, but some left-hand circular polarization was observed implyi…