Search Publications

Do coronal mass ejections implode in the solar wind?
DOI: 10.1029/98GL01057 Bibcode: 1998GeoRL..25.1529R

Riley, Pete; Gosling, J. T.

Ulysses observations show that many coronal mass ejections observed at high heliographic latitudes expand because they initially have higher internal pressures than that of the surrounding solar wind. This expansion commonly drives a shock wave into the ambient wind in all directions. In the analogous process of an explosion in the Earth's atmosph…

1998 Geophysical Research Letters
Ulysses 27
A pair of forward and reverse slow-mode shocks detected by Ulysses at ∼5 AU
DOI: 10.1029/98GL02014 Bibcode: 1998GeoRL..25.2613H

Lakhina, G. S.; Tsurutani, B. T.; Smith, E. J. +6 more

We report the first finding of a pair of forward and reverse slow-mode shocks in the distant heliosphere using plasma and magnetic field data from the Ulysses spacecraft located at 5.3 AU and 9°S heliolatitude. The slow-mode shocks are found to occur in a compressed magnetic field (low plasma ) region within a co-rotating interaction region (CIR).…

1998 Geophysical Research Letters
Ulysses 22
Wind-Ulysses source location of radio emissions associated with the January 1997 coronal mass ejection
DOI: 10.1029/98GL00571 Bibcode: 1998GeoRL..25.2497H

Maksimovic, M.; Kaiser, M. L.; Bougeret, J. -L. +2 more

We investigate the 3-D source location of interplanetary type Il-like radio bursts from observations involving two spacecraft. Uncommon type II radio emissions were observed simultaneously on 8 January 1997 by the Wind and Ulysses spacecraft and are believed to be associated with the Interplanetary Coronal Mass Ejection detected on 6-7 January by …

1998 Geophysical Research Letters
Ulysses 21
The symmetry of the heliospheric current sheet as observed by Ulysses during the Fast Latitude Scan
DOI: 10.1029/97GL53699 Bibcode: 1998GeoRL..25..245E

Balogh, André; Erdős, Géza

The position of the heliospheric current sheet is investigated, based on Ulysses observations during the fast latitude scan from the South pole (in September, 1994) to the North pole (in July, 1995). The location of the current sheet on the source surface was calculated by mapping back the magnetic field vectors measured by Ulysses along the solar…

1998 Geophysical Research Letters
Ulysses 20
Synoptic measurements of Martian winds using the Hubble Space Telescope
DOI: 10.1029/98GL50358 Bibcode: 1998GeoRL..25..611M

Crisp, David; Bell, James F., III; Mischna, Michael A. +1 more

We used the Hubble Space Telescope to make wind speed and wind direction measurements of the Martian atmosphere during early northern summer (Ls=97°). Our strategy utilized a series of near-UV images with optimal temporal sampling to track observable cloud features and to determine the direction and speed of cloud motion. Several techni…

1998 Geophysical Research Letters
eHST 11
Ulysses and WIND particle observations of the November 1997 solar events
DOI: 10.1029/98GL52667 Bibcode: 1998GeoRL..25.3469L

Lario, D.; Balogh, A.; Maksimovic, M. +5 more

The episode of intense solar activity on 4 and 6 November 1997 resulted in large and extended particle events observed by the Ulysses and WIND spacecraft. Ulysses was at a heliocentric distance of 5.34 AU, very close to the solar equator and 100° west in heliolongitude from earth. WIND was near the earth at 0.99 AU from the Sun and in the ecliptic…

1998 Geophysical Research Letters
Ulysses 11
Quasi-periodic behavior of ion events and wave activity upstream from Jupiter's Bow Shock: Ulysses' observations
DOI: 10.1029/98GL00988 Bibcode: 1998GeoRL..25.1533A

Balogh, A.; Sarris, E. T.; Anagnostopoulos, G. C. +3 more

A new insight into the ways that the Jovian magnetosphere influences the near Jupiter interplanetary space becomes possible thanks to Ulysses' collection of magnetic field, plasma and energetic ion (HI-SCALE) data during its inbound trajectory (d22-d34, 1992). The most striking new results from the analysis of those data are the following: a) pres…

1998 Geophysical Research Letters
Ulysses 10
Jovian radio “bullseyes” observed by Ulysses
DOI: 10.1029/98GL02255 Bibcode: 1998GeoRL..25.3113K

MacDowall, R. J.; Kaiser, M. L.

We report the observation of extremely rare semi-bullseye or target-like features in the dynamic spectra of Jupiter obtained in 1991-1994 by the Ulysses Unified Radio and Plasma wave instrument. The emissions lie in the 20-50 kHz band and consist of narrow band (∼1-2 kHz) semi-concentric wisps on frequency-time dynamic spectra. The individual wisp…

1998 Geophysical Research Letters
Ulysses 9
Interstellar pickup hydrogen observations at large heliocentric distances
DOI: 10.1029/97GL03785 Bibcode: 1998GeoRL..25..241M

Gazis, P. R.; Mihalov, J. D.

Possible signatures of interstellar pickup hydrogen have been identified in data from the Pioneer 10 and 11 Ames plasma analyzers at locations out to beyond the orbit of Saturn, and at a wide range of longitudes in the heliosphere, both upstream and downstream in the interstellar wind. These signatures provide an extension of pickup ion observatio…

1998 Geophysical Research Letters
Ulysses 9
Polar plumes and fine-scale coronal structures - On the interpretation of coronal radio sounding data
DOI: 10.1029/98GL51052 Bibcode: 1998GeoRL..25.1845P

Pätzold, M.; Bird, M. K.

Variations in total electron content at high heliographic latitudes, observed during the 1995 solar conjunction of the Ulysses spacecraft when the radio ray path was embedded in the southern coronal hole, were interpreted by Woo and Habbal [1997b] as polar plume structures extending to at least 30 solar radii from the Sun. Somewhat surprisingly, w…

1998 Geophysical Research Letters
Ulysses 5