Search Publications

On the rotational dynamics of Prometheus and Pandora
DOI: 10.1007/s10569-008-9131-z Bibcode: 2008CeMDA.101...31M

Melnikov, A. V.; Shevchenko, I. I.

Possible rotation states of two satellites of Saturn, Prometheus (S16) and Pandora (S17), are studied by means of numerical experiments. The attitude stability of all possible modes of synchronous rotation and the motion close to these modes is analyzed by means of computation of the Lyapunov spectra of the motion. The stability analysis confirms …

2008 Celestial Mechanics and Dynamical Astronomy
Cassini 14
Modeling magnetohydrodynamics and non-equilibrium SoHO/UVCS line emission of CME shocks
DOI: 10.1051/0004-6361:20079088 Bibcode: 2008A&A...481..835P

Raymond, J. C.; Orlando, S.; Reale, F. +1 more

Aims: We provide a guideline to interpret the UltraViolet Coronograph Spectrometer (UVCS) emission lines (in particular O VI and Si XII) during shock wave propagation in the outer solar corona.
Methods: We use a numerical magnetohydrodynamic (MHD) model performing a set of simulations of shock waves generated in the corona and from the result …

2008 Astronomy and Astrophysics
SOHO 14
Detecting transits from Earth-sized planets around Sun-like stars
DOI: 10.1051/0004-6361:20079268 Bibcode: 2008A&A...485..607C

Fridlund, M.; Carpano, S.

Context: Detecting regular dips in the light curve of a star is an easy way to detect the presence of an orbiting planet. CoRoT is a Franco-European mission launched at the end of 2006, and one of its main objectives is to detect planetary systems using the transit method.
Aims: In this paper, we present a new method for transit detection and …

2008 Astronomy and Astrophysics
SOHO 14
Tilts and polarity separation in the sunspot groups and active regions at the ascending and descending phases of the cycle 23
DOI: 10.1016/j.asr.2007.02.082 Bibcode: 2008AdSpR..41..881Z

Zharkova, V. V.; Zharkov, S. I.

The Solar Feature Catalogues for sunspots and active regions measured with SOHO/MDI instrument and Ca II K3 spectroheliograph of the Paris-Meudon Observatory are analyzed with the automated classification technique for sunspot groups and active region polarities. We report the first classification results for daily variations of tilt angles (norma…

2008 Advances in Space Research
SOHO 14
Longitudinal plasma density variations at Saturn caused by hot electrons
DOI: 10.1029/2007GL031095 Bibcode: 2008GeoRL..35.3107D

Delamere, P. A.; Bagenal, F.

A non-thermal tail to the electron distribution function has been measured in the inner magnetospheres of both Jupiter and Saturn. These ``hot'' electrons are only a small fraction (<1%) of the total electron density, yet their influence on the gas tori at Jupiter and Saturn is significant. We explore the role of hot electrons in both systems u…

2008 Geophysical Research Letters
Cassini 13
Asteroid 2867 Steins. I. Photometric properties from OSIRIS/Rosetta and ground-based visible observations
DOI: 10.1051/0004-6361:20078994 Bibcode: 2008A&A...487.1171J

Jorda, L.; Lamy, P. L.; Barucci, M. A. +6 more

Context: Asteroid 2867 Steins is the first target of the Rosetta space mission with a flyby scheduled in September 2008.
Aims: An early characterization is needed to optimize the flyby parameters and the science operations and to maximize the scientific return. The aim of this article is to characterize the photometric properties of this aster…

2008 Astronomy and Astrophysics
Rosetta 13
Statistics of young starforming complexes in spiral galaxies using NIR photometry
DOI: 10.1051/0004-6361:200810222 Bibcode: 2008A&A...490...87G

Dottori, H.; Grosbøl, P.

Aims: Very young stellar clusters and cluster complexes may be embedded in dust lanes along spiral arms in disk galaxies and escape detection in visual bands. Observations in the near-infrared K-band offer an almost unbiased view of such clusters or complexes due to the small attenuation by dust at this wavelength. The objective is to determine th…

2008 Astronomy and Astrophysics
eHST 13
A Multiwavelength Analysis of the Halo Planetary Nebula DdDm-1
DOI: 10.1086/588460 Bibcode: 2008ApJ...680.1162H

Dufour, R. J.; Henry, R. B. C.; Kwitter, K. B. +1 more

We present new HST optical imagery as well as new UV and IR spectroscopic data obtained with the Hubble Space Telescope and Spitzer Space Telescope, respectively, of the halo planetary nebula DdDm-1. For the first time we present a resolved image of this object, which indicates that the morphology of DdDm-1 can be described as two orthogonal ellip…

2008 The Astrophysical Journal
eHST 13
Ion Anisotropy and High-Energy Variability of Large Solar Particle Events: A Comparative Study
DOI: 10.1086/533490 Bibcode: 2008ApJ...678.1471T

Reames, Donald V.; Tan, Lun C.; Ng, Chee K.

We have made comparative studies of ion anisotropy and high-energy variability of solar energetic particle (SEP) events previously examined by the Solar, Heliospheric, and Interplanetary Environment (SHINE) Workshop campaign. We have found distinctly different characteristics of SEPs in two large "gradual" events having very similar solar progenit…

2008 The Astrophysical Journal
SOHO 13
Multi-epoch spectroscopy of the globular cluster black hole in NGC 4472
DOI: 10.1111/j.1365-2966.2008.13158.x Bibcode: 2008MNRAS.386.2075S

Maccarone, T. J.; Kundu, A.; Zepf, S. E. +1 more

We present a study of the X-ray spectral properties of the highly variable X-ray emitting black hole in a globular cluster in the elliptical galaxy NGC 4472. The X-ray Multiple Mirror-Newton (XMM-Newton) spectrum of the source in its bright epoch is well described by a multiple blackbody model with a characteristic temperature kTin ~ 0.…

2008 Monthly Notices of the Royal Astronomical Society
XMM-Newton 13