Search Publications

Discovery of Jovian dust streams and interstellar grains by the Ulysses spacecraft
DOI: 10.1038/362428a0 Bibcode: 1993Natur.362..428G

Forsyth, R.; Balogh, A.; Bame, S. J. +20 more

ON 8 February 1992, the Ulysses spacecraft flew by Jupiter at a distance of 5.4 AU from the Sun. During the encounter, the spacecraft was deflected into a new orbit, inclined at about 80° to the ecliptic plane, which will ultimately lead Ulysses over the polar regions of the Sun1. Within 1 AU from Jupiter, the onboard dust de…

1993 Nature
Ulysses 336
Mechanism for the acceleration and ejection of dust grains from Jupiter's magnetosphere
DOI: 10.1038/363144a0 Bibcode: 1993Natur.363..144H

Horanyi, M.; Grun, E.; Morfill, G.

PERHAPS the most unexpected finding of the Ulysses mission so far has been the detection of quasi-periodic streams of high-velocity, submicrometre-sized dust particles during the spacecraft's encounter with Jupiter1. The impact geometry clearly shows that these small grains originate in the jovian system, but it is surprising that any d…

1993 Nature
Ulysses 242
A large nuclear accretion disk in the active galaxy NGC4261
DOI: 10.1038/364213a0 Bibcode: 1993Natur.364..213J

O'Connell, Robert W.; Ferrarese, Laura; Ford, Holland C. +2 more

THE powerful emissions from the nuclei of active galaxies and quasars are thought to arise from the accretion of matter onto a massive black hole. Angular momentum will prevent matter from falling directly onto the central mass; instead, an 'accretion disk' should form, within which the gravitationally bound material will lose angular momentum and…

1993 Nature
eHST 151
Detection of the hydroxyl radical in the Saturn magnetosphere
DOI: 10.1038/363329a0 Bibcode: 1993Natur.363..329S

Shemansky, D. E.; Tripp, T. M.; Matheson, P. +2 more

THE magnetosphere in the vicinity of the orbits of Saturn's icy satellites consists of a low-density plasma, in which the electrons are an order of magnitude cooler than the accompanying heavy ions1. Most models2-12 neglect this fact, even though radiative cooling and diffusive loss rates are both too slow to account for the …

1993 Nature
eHST 139
Ejection of dust from Jupiter's gossamer ring
DOI: 10.1038/364695a0 Bibcode: 1993Natur.364..695H

Hamilton, Douglas P.; Burns, Joseph A.

ONE of the most intriguing discoveries of the Ulysses mission so far has been the detection of periodic, collimated streams of high-velocity, submicrometre-sized dust particles emanating from Jupiter1,2. To explain the Ulysses data, Horanyi et al. showed3 that electromagnetic forces within Jupiter's magnetosphere can accelera…

1993 Nature
Ulysses 65
Dust particle impacts during the Giotto encounter with comet Grigg-Skjellerup
DOI: 10.1038/362732a0 Bibcode: 1993Natur.362..732M

Colangeli, L.; Green, S. F.; Greenberg, J. M. +7 more

IN the European Space Agency's 1992 Giotto Extended Mission, the Dust Impact Detection System operated successfully during a fly-by that took the spacecraft within about 200 km of the nucleus of comet Grigg-Skjellerup. During the encounter, three meteoroid impacts were detected on Giotto's front shield. The particle masses were found to be lOO

1993 Nature
Giotto 61
Internal structure and polarization of the optical jet of the quasar 3C273
DOI: 10.1038/365133a0 Bibcode: 1993Natur.365..133T

Mackay, C. D.; Thomson, R. C.; Wright, A. E.

THE extragalactic radio source 3C273 was the first quasar to be identified1, and remains one of the nearest and most luminous quasars known. In radio images2-4, it appears as a bright, point-like nucleus from which emerges a single large jet; the jet is also apparent in optical images5-8, but the relatively poor re…

1993 Nature
eHST 57