Search Publications
HST observations of spokes in Saturn's B ring
French, Richard G.; Salo, Heikki J.; Dones, Luke +3 more
As part of a long-term study of Saturn's rings, we have used the Hubble Space Telescope's (HST) Wide Field and Planetary Camera (WFPC2) to obtain several hundred high resolution images from 1996 to 2004, spanning the full range of ring tilt and solar phase angles accessible from the Earth. Using these multiwavelength observations and HST archival …
Observations of an Emerging Flux Region Surge: Implications for Coronal Mass Ejections Triggered by Emerging Flux
Liu, Y.; Su, J. T.; Shibata, K. +2 more
It is well known that coronal mass ejections (CMEs) are often associated with flares and filament eruptions. Previous studies of CMEs, however, have not established any association between CMEs and surges. In this paper, we present a detailed analysis of a large emerging flux region (EFR) surge and a jetlike CME, both observed on 1998 April 16. Ou…
Transition from substorm growth to substorm expansion phase as observed with a radial configuration of ISTP and Cluster spacecraft
Sauvaud, J. -A.; Thomsen, M. F.; Klecker, B. +10 more
Transition from the growth phase to the substorm expansion during a well-isolated substorm with a strong growth phase is investigated using a unique radial (THEMIS-like) spacecraft constellation near midnight, including the probing of the tail current at ~16 RE with Cluster, of the transition region at ~9 RE with Geotail and …
Cluster Observes the High-Altitude CUSP Region
Lundin, R.; Sauvaud, J. -A.; Escoubet, C. P. +18 more
This paper gives an overview of Cluster observations in the high-altitude cusp region of the magnetosphere. The low and mid-altitude cusps have been extensively studied previously with a number of low-altitude satellites, but only little is known about the distant part of the magnetospheric cusps. During the spring-time, the trajectory of the Clus…
Bimodal Galaxies and Bimodality in Globular Cluster Systems
Forbes, Duncan A.
Various galaxy properties are not continuous over a large range in mass but rather reveal a remarkable transition or ``bimodality'' at a stellar mass of 3×1010 Msolar. These properties include colors, stellar populations, X-ray emission, and mass-to-light ratios. This behavior has been interpreted as the transition from hot t…
Prominence atlas in the SUMER range 800-1250 Å. II. Line profile properties and ions identifications
Vial, J. -C.; Parenti, S.; Lemaire, P.
We present a SOHO/SUMER spectral atlas in the 800-1250 Å range of a prominence and a Quiet Sun (QS) region observed in 1999. The atlas is produced for two separate areas of the prominence. The QS spectrum is used as a reference. This is the first prominence atlas obtained with high spectral resolution (≈0.044 Å). It provides information concerning…
The lens and source of the optical Einstein ring gravitational lens ER 0047-2808
Lewis, Geraint F.; Warren, Stephen J.; Hewett, Paul C. +1 more
We perform a detailed analysis of the optical gravitational lens ER 0047-2808 imaged with the Wide Field Planetary Camera 2 on the Hubble Space Telescope. Using software specifically designed for the analysis of resolved gravitational lens systems, we focus on how the image alone can constrain the mass distribution in the lens galaxy. We find that…
The global plasma environment of Titan as observed by Cassini Plasma Spectrometer during the first two close encounters with Titan
Coates, A. J.; Crary, F.; Johnson, R. E. +17 more
The Cassini spacecraft flew by Titan on October 26, 2004 and December 13, 2004. In both cases it entered the ionosphere of Titan, allowing exploration of its plasma environment. Using observations from the Cassini Plasma Spectrometer (CAPS) and the Cassini magnetometer along the inbound legs of both flybys, we examine Titan's global plasma environ…
Interplanetary conditions and magnetospheric dynamics during the Cassini orbit insertion fly-through of Saturn's magnetosphere
Jackman, C. M.; Kurth, W. S.; Cecconi, B. +5 more
The primary purpose of this paper is to discuss the interplanetary conditions that prevailed during the Saturn orbit insertion (SOI) fly-through of Saturn's magnetosphere by the Cassini spacecraft in June-July 2004 and the consequent magnetospheric dynamics. We begin by examining concurrent interplanetary magnetic field (IMF) and Saturn kilometric…
Dynamics of solar active regions. II. Oscillations observed with MDI and their relation to the magnetic field topology
Muglach, K.; Staude, J.; Hofmann, A.
We present new results of an international joint observing campaign, which was carried out in September 2000 to study the oscillatory behaviour of solar active regions. We concentrate on oscillations in the lower layers of the solar atmosphere as observed with the Michelson Doppler Imager (MDI, Scherrer et al. 1995, Sol. Phys., 162, 129). The resu…