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1995 observations of Martian dust storms using the Hubble Space Telescope
Bell, James F., III; Wolff, Michael J.; Clancy, R. Todd +3 more
A synoptic monitoring program of Mars using the Wide Field Planetary Camera 2 on board the Hubble Space Telescope has resulted in the observation of discrete dust activity for two dates following the 1995 opposition. Data obtained on April 8 (LS=82°) and August 21, 1995 (LS=145°) reveal the presence of local dust storms in th…
Ulysses observations of wave activity at interplanetary shocks and implications for type II radio bursts
MacDowall, R. J.; Phillips, J. L.; Stone, R. G. +2 more
We present the first quantitative investigation of interplanetary type II radio emission in which in situ waves measured at interplanetary shocks are used to compute radio wave intensities for comparison with type II observations. This study is based on in situ measurements of 42 in-ecliptic forward shocks as well as 10 intervals of type II emissi…
Excess heating of 4He2+ and O6+ relative to H+ downstream of interplanetary shocks
Mall, Urs; Gloeckler, George; Geiss, Johannes +1 more
Using observations made by the solar wind ion composition spectrometer on Ulysses during its trip in the ecliptic plane to Jupiter, we examined the temperature ratios T(4He2+)/T(H+) and T(O6+)/T(H+) across 15 shocks, including forward and reverse shock pairs as well as isolated shocks. The mea…
Detection of Bernstein wave forbidden bands in the Jovian magnetosphere: A new way to measure the electron density
Forsyth, R. J.; Moncuquet, Michel; Meyer-Vernet, Nicole +2 more
We analyze the power spectra measured by the radio receiver of the Unified Radio and Plasma Wave experiment on Ulysses during its passage through the Jovian inner magnetosphere from ~9RJ in the outskirts of the Io plasma torus to ~13RJ near the plasma sheet. Below the plasma frequency fp, these spectra are weakly b…
Bow shock analysis at comets Halley and Grigg-Skjellerup
Coates, A. J.; Neubauer, F. M.; Mazelle, C.
The interaction of an active comet with the solar wind is effected by the pickup of heavy cometary ions over extended regions of space. It was predicted before any spacecraft encounters with comets that a bow shock would form at a critical point in the mass-loaded flow. Here we present an analysis of the results from Giotto's encounters of comets …
An estimate of large-scale solar wind density and velocity profiles in a coronal hole and the coronal streamer belt
Tsurutani, Bruce T.; Pätzold, Martin; Bird, Michael K.
With the use of the total electron content data obtained by the Ulysses Solar Corona Experiment (SCE) during the first solar conjunction in summer 1991, two data sets were selected, one associated with a coronal hole and the other associated with coronal streamer belt crossings. To determine a large-scale coronal streamer belt density profile, the…
Reappearance of recurrent low-energy particle events at Ulysses/HI-SCALE in the northern heliosphere
Simnett, G. M.; Lanzerotti, L. J.; Armstrong, T. P. +4 more
In the high-latitude northern hemisphere of the heliosphere, the Heliosphere Instrument for Spectra Composition and Anisotropy at Low Energies (HI-SCALE) energetic particle detectors on Ulysses have measured quasi-recurrent ~26-day increases of 40-65 keV electrons during 11 solar rotations from October 1995 through July 1996. They do not appear on…
Solar wind proton flux latitudinal variations: Comparison between Ulysses in situ data and indirect measurements from interstellar Lyman α mapping
Lallement, Rosine; Quémerais, Eric; Summanen, Tuula
We compare the solar wind proton flux latitude dependence derived in the past from the interstellar neutral H distribution in the inner heliosphere from Lyman α observations with recent ``in situ'' solar wind observations by Ulysses [Goldstein et al., 1995, Phillips et al., 1995, 1996, J. L. Phillips, private communication, 1996]. We find common f…
Trapped energetic ions in Jupiter's inner magnetosphere
Anglin, J. D.; Burrows, J. R.; Mu, J. L. +1 more
Ion measurements made with the high-flux telescope at ~1MeV/nucleon during the passage of the Ulysses spacecraft through Jupiter's inner magnetosphere are presented. Stable pancake-shaped pitch angle distributions were observed for protons inside ~17RJ. They are fitted by a time-independent model in which an assumed directional flux at …
Alfvénic fluctuations in fast and slow solar winds
Orlando, S.; Peres, G.; Rosner, R. +1 more
We compute properties of Alfvénic fluctuations within a wide frequency range (i.e., 10-6s-1<~f<~10-2s-1) in both high- and low-speed magnetized radial solar winds. In particular, the radial and frequency variations of the normalized cross helicity σc, the Alfvén ratio <script>R<…