Publication archive

Publication archive

Nearly four years after its launch by the Space Shuttle 'Discovery', the European-built spacecraft reached the most southerly point on its out-of-ecliptic orbit, 80.2 degrees south of the Sun's equator, at a distance of 2.3 AU (345 million km) from the Sun. Although it will take scientists many months to unravel fully the new and exciting data acquired by Ulysses, several important results have already emerged.
Published: 02 April 1995
In this article, we summarise the key findings of the mission to date, and discuss the exciting results to be expected from the second phase of Ulysses' out-of-ecliptic journey.
Published: 01 November 1997
Published: 01 December 1996
The articles that comprise this special issue are devoted to recent results from the high-latitude passes of Ulysses, including the rapid transit from the southern to the northern hemisphere. This paper serves as an introduction to these articles, and provides a short summary of the major scientific findings from the mission to date. Also included is a description of the various Ulysses data archives and their access.
Published: 01 December 1996
The year 2000 promises to be highly eventful for the joint ESA-NASA Ulysses mission. Not only does it mark an important anniversary - on 6 October, Ulysses will have been in orbit for 10 years - it also sees the return of Ulysses to the poles of the Sun. Given the spectacular success of the spacecraft's first visit to these previously unexplored regions in 1994/95, there is every reason to expect a rich scientific harvest once again.
Published: 02 July 2000
Several articles in this Special Issue of the Astronomy and Astrophysics Supplement Series were devoted to the Ulysses mission and its payload.
Published: 01 January 1992
For this article there is no abstract available online. The link below will take you the the Geophysical Research Letters homepage, where you can subscribe to the journal.
Published: 01 December 1995

Remote sensing observations and the direct sampling of material from a few comets have established the characteristic composition of cometary gas. This gas is ionized by solar ultraviolet radiation and the solar wind to form 'pick-up' ions, ions in a low ionization state that retain the same compositional signatures as the original gas.

The pick-up ions are carried outward by the solar wind, and they could in principle be detected far from the coma. (Sampling of pick-up ions has also been used to study interplanetary dust, Venus' tail and the interstellar medium.)

Here we report the serendipitous detection of cometary pick-up ions, most probably associated with the tail of comet Hyakutake, at a distance of 3.4 au from the nucleus. Previous observations have provided a wealth of physical and chemical information about a small sample of comets, but this detection suggests that remote sampling of comet compositions, and the discovery of otherwise invisible comets, may be possible.

Published: 07 April 2000
Observations of the varying orientations of comet tails led to the suggestion of the existence of the solar wind - a continuous outflow of ionized material from the Sun. It is now well established that gas from comets is ionized by several processes and joins the solar wind, forming an ion (plasma) tail that points away from the Sun. The plasma environments of three comets have been measured in situ, but only in the upstream direction or less than 8,000 km downstream of the nucleus. Here we report a fortuitous crossing by a spacecraft of the plasma tail of comet Hyakutake (C/1996 B2), at a distance of more than 3.8 astronomical units (550 million kilometres) from its nucleus. This surpasses the tail length of 2 au determined for the Great March Comet of 1843 (C/1843 D1). Our measurements reveal that, at this distance, the tail of comet Hyakutake was a structured entity at least 7 million kilometres in diameter.
Published: 07 April 2000
— 20 Items per Page
Showing 21 - 30 of 30 results.
11-Aug-2020 04:37 UT

ShortUrl Portlet

Shortcut URL

https://sci.esa.int/p/jwRkaGW