Search Publications
In ecliptic observations of Jovian radio emissions by Ulysses comparison with Voyager results
MacDowall, R. J.; Kaiser, M. L.; Desch, M. D. +6 more
During the Ulysses inbound cruise to Jupiter the Unified Radio and Plasma Wave (URAP) experiment observed a variety of the planet's radio components in the frequency range below 1 MHz. Most of these emissions were already detected by the Voyager Radio Astronomy (PRA) and Plasma Wave (PWS) experiments, however with much less sensitivity and differe…
Solar wind thermal electrons in the ecliptic plane between 1 and 4 AU: Preliminary results from the Ulysses radio receiver
MacDowall, R. J.; Bougeret, J. -L.; Stone, R. G. +8 more
The radio receiver of the Unified Radio and Plasma (URAP) experiment aboard the Ulysses spacecraft records spectra of the quasi-thermal plasma noise. The interpretation of these spectra allows the determination of the total electron density Ne and of the cold (core) electron temperature Tc in the solar wind. A single power law does not fit the var…
Non-relativistic solar electron events during December 1990: Results from Ulysses
Chaizy, P.; Anderson, K. A.; Lin, R. P. +1 more
Several groups of impulsive flare accelerated non-relativistic solar electron events occurred in November and December 1990. In a total of 18 separate events, most show the characteristic dispersion in arrival times at the Ulysses spacecraft corresponding to travel time for the various particle energy groups. After maximum development, the electro…
Predictions of the solar wind interaction with Comet Grigg-Skjellerup
Coates, A. J.; Johnstone, A. D.; Huddleston, D. E.
The planned encounter of the Giotto spacecraft with comet Grigg-Skjellerup on 10th July 1992 promises to extend our knowledge of the solar wind interaction with comets substantially. While there have been spacecraft missions to comets before now, this mission is exploratory in the sense that the target comet is much older and therefore it has a mu…
Solar energetic and shock-accelerated particles observed between 1 and 4 AU by the Kiel Electron Telescope (KET) on board Ulysses
Sierks, H.; Kunow, H.; Wibberenz, G. +6 more
We present observations of solar energetic particles and shock-accelerated particles observed by the Kiel Electron Telescope (KET) on board the Ulysses spacecraft in the time interval 26 October 1990 to mid November 1991. Prompt events with diffusive propagation were observed mainly at small radial distances while at larger distances shock-related…
A model of convection and corotation in Jupiter's magnetosphere: Ulysses predictions
Cheng, A. F.
The Ulysses Jupiter encounter will include the first spacecraft pass through the dusk magnetosphere and will allow new tests of Jovian convection and corotation models. The Cheng and Krimigis [1989] model is extended to suggest that corotation lag occurs principally within the magnetodisk proper, which extends out to ∼60-70 RJ. It is pr…
Ulysses particle observations of the March 1991 solar flare events
Heras, A. M.; Forsyth, R.; Balogh, A. +4 more
We present observations of energetic ions from the COSPIN instrument on the Ulysses spacecraft at 2.5 AU during the March 1991 series of solar flare events. The intensity profiles observed during this sequence of events were affected both by the presence of interplanetary shocks and large-scale discontinuities in the magnetic field, the low-energy…
The Ulysses Mission: In-ecliptic phase
Smith, E. J.; Wenzel, K. -P.
The Ulysses mission is unique in the history of the exploration of our solar system by spacecraft. The path followed by Ulysses will enable us, for the first time, to explore the heliosphere within a few astronomical units of the Sun over the full range of heliographic latitudes. The mission, a collaboration between ESA and NASA, was launched on 6…
Jovian Bremsstrahlung X rays: A Ulysses prediction
Stern, S. A.; Hurley, K. C.; Sommer, M. +2 more
The Jovian aurora is the most powerful planetary aurora in the solar system; to date, however, it has not been possible to establish conclusively which mechanisms are involved in the excitation of the auroral emissions that have been observed at ultraviolet, infrared, and soft X ray wavelengths. Precipitation of Iogenic heavy sulfur and oxygen ion…
Ion-cyclotron waves at Jupiter: Possibility of detection by Ulysses
Horne, Richard B.; Thorne, Richard M.; Mei, Yi
We evaluate the convective growth of ion-cyclotron waves in the Io plasma torus using realistic plasma parameters. Significant wave amplification is restricted to two dominant frequency bands. As originally proposed by Thorne and Moses [1983,1985], waves between the O+ and H+ gyro-frequencies may be excited at higher latitude…