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Hubble Space Telescope Observations of Comet P/Shoemaker-Levy 9 (1993e)

Feldman, P. D.; A'Hearn, M. F.; Weaver, H. A. +16 more

The Hubble Space Telescope observed the fragmented comet P/Shoemaker-Levy 9 (1993e) (P indicates that it is a periodic comet) on 1 July 1993. Approximately 20 individual nuclei and their comae were observed in images taken with the Planetary Camera. After subtraction of the comae light, the 11 brightest nuclei have magnitudes between ~23.7 and 24.…

A Remarkable Auroral Event on Jupiter Observed in the Ultraviolet with the Hubble Space Telescope

Paresce, F.; Waite, J. H.; Grodent, D. +7 more

Two sets of ultraviolet images of the Jovian north aurora were obtained with the Faint Object Camera on board the Hubble Space Telescope. The first series shows an intense discrete arc in near corotation with the planet. The maximum apparent molecular hydrogen emission rate corresponds to an electron precipitation of ~1 watt per square meter, whic…

Seeing the Nuclei of Active Galaxies

Kinney, Anne L.

The Case of the Blue Stragglers

Bailyn, Charles

Detection of Interstellar Pick-Up Hydrogen in the Solar System

Balsiger, H.; Geiss, J.; Galvin, A. B. +6 more

Interstellar hydrogen ionized primarily by the solar wind has been detected by the SWICS instrument on the Ulysses spacecraft at a distance of 4.8 astronomical units from the sun. This "pick-up" hydrogen is identified by its distinct velocity distribution function, which drops abruptly at twice the local solar wind speed. From the measured fluxes …

Deceleration of Interstellar Hydrogen at the Heliospheric Interface

Bertaux, Jean-Loup; Clarke, John T.; Lallement, Rosine

High-resolution spectra of nearby stars show absorption lines due to material in the local interstellar cloud. This cloud is deduced to be moving at 26 kilometers per second with respect to the sun, and in the same direction as the "interstellar wind" flowing through the solar system. Measurements by the Ulysses spacecraft show that neutral helium…

The Drift of Saturn's North Polar Spot Observed by the Hubble Space Telescope

Caldwell, J.; Hua, X. -M.; Turgeon, B. +2 more

Polar projections of 50 images of Saturn at 889 nanometers and 25 images at 718 nanometers taken by the Hubble Space Telescope in November 1990, as well as 3 images at each wavelength taken in June 1991, have been examined. Among them, 31 show the north polar spot, which is associated with Saturn's polar hexagon, in locations suitable for measurem…

Magnetic Field Observations During the Ulysses Flyby of Jupiter

Dougherty, M. K.; Balogh, A.; Tsurutani, B. T. +5 more

The Jovian flyby of the Ulysses spacecraft presented the opportunity to confirm and complement the findings of the four previous missions that investigated the structure and dynamics of the Jovian magnetosphere and magnetic field, as well as to explore for the first time the high-latitude dusk side of the magnetosphere and its boundary regions. In…

Ulysses Radio and Plasma Wave Observations in the Jupiter Environment

Goetz, K.; Kellogg, P. J.; MacDowall, R. J. +23 more

The Unified Radio and Plasma Wave (URAP) experiment has produced new observations of the Jupiter environment, owing to the unique capabilities of the instrument and the traversal of high Jovian latitudes. Broad-band continuum radio emission from Jupiter and in situ plasma waves have proved valuable in delineating the magnetospheric boundaries. Sim…

Jupiter's Magnetosphere: Plasma Description from the Ulysses Flyby

Goldstein, Bruce E.; Neugebauer, Marcia; Thomsen, Michelle F. +7 more

Plasma observations at Jupiter show that the outer regions of the Jovian magnetosphere are remarkably similar to those of Earth. Bow-shock precursor electrons and ions were detected in the upstream solar wind, as at Earth. Plasma changes across the bow shock and properties of the magnetosheath electrons were much like those at Earth, indicating th…