Search Publications
Saturn's rotation period from its atmospheric planetary-wave configuration
Read, P. L.; Dowling, T. E.; Schubert, G.
The rotation period of a gas giant's magnetic field (called the System III reference frame) is commonly used to infer its bulk rotation. Saturn's dipole magnetic field is not tilted relative to its rotation axis (unlike Jupiter, Uranus and Neptune), so the surrogate measure of its long-wavelength (kilometric) radiation is currently used to fix the…
Hinode Observation of the Magnetic Fields in a Sunspot Light Bridge Accompanied by Long-Lasting Chromospheric Plasma Ejections
Tsuneta, Saku; Shimizu, Toshifumi; Lites, Bruce W. +7 more
We present high-resolution magnetic field measurements of a sunspot light bridge (LB) that produced chromospheric plasma ejections intermittently and recurrently for more than 1 day. The observations were carried out with the Hinode Solar Optical Telescope on 2007 April 29 and 30. The spectro-polarimeter reveals obliquely oriented magnetic fields …
Heavy ions, temperatures and winds in Titan's ionosphere: Combined Cassini CAPS and INMS observations
Young, D. T.; Waite, J. H.; Magee, B. A. +3 more
Multiple Titan encounters by the Cassini spacecraft have shown that ion chemistry in Titan's upper atmosphere is much more complex than previously thought. As well as showing a great variety of species present below 100 amu, they also include the detection of negative ions and of large abundances of ions above 100 amu. Here, we use data from two C…
Signatures of Alfvén waves in the polar coronal holes as seen by EIS/Hinode
Doyle, J. G.; Banerjee, D.; Pérez-Suárez, D.
Context: We diagnose the properties of the plume and interplume regions in a polar coronal hole and the role of waves in the acceleration of the solar wind.
Aims: We attempt to detect whether Alfvén waves are present in the polar coronal holes through variations in EUV line widths.
Methods: Using spectral observations performed over a pola…
The Environments of High-Redshift Quasi-Stellar Objects
Panagia, N.; Stiavelli, Massimo; Djorgovski, S. G. +9 more
We present a sample of i 775-dropout candidates identified in five Hubble Advanced Camera for Surveys (ACS) fields centered on Sloan Digital Sky Survey quasi-stellar objects (QSOs) at redshift z ~ 6. Our fields are as deep as the GOODS ACS images, which are used as a reference field sample. We find them to be overdense in two fields, un…
Quantitative compositional analysis of martian mafic regions using the MEx/OMEGA reflectance data. 2. Petrological implications
Mangold, N.; Bibring, J. -P.; Gondet, B. +8 more
The primary objectives of this paper are to determine the modal mineralogy of selected low albedo terrains of different ages ranging from Noachian to Amazonian exposed on the surface of Mars. This analysis is conducted using the spectral modeling of the Observatoire pour la Minéralogie, l'Eau, les Glaces, et l'Activité (OMEGA) reflectance data. Re…
A Population of Compact Elliptical Galaxies Detected with the Virtual Observatory
Revaz, Yves; Micol, Alberto; Chilingarian, Igor +5 more
Compact elliptical galaxies are characterized by small sizes and high stellar densities. They are thought to form through tidal stripping of massive progenitors. However, only a handful of them were known, preventing us from understanding the role played by this mechanism in galaxy evolution. We present a population of 21 compact elliptical galaxi…
Global pattern of Titan's dunes: Radar survey from the Cassini prime mission
Lorenz, Ralph D.; Radebaugh, Jani
We present a map of the orientation and extent of Titan's sand dunes derived from the complete radar imaging dataset from the Cassini prime mission. The 16,000 dune segments we have mapped cover ~8% of the Titan's surface (suggesting a total coverage of ~20%), are confined within 30° of the equator, and show local and regional deviations of dune o…
Short-lived spots in solar-like stars as observed by CoRoT
Auvergne, M.; Baudin, F.; Baglin, A. +4 more
Context: CoRoT light curves have an unprecedented photometric quality, having simultaneously a high signal-to-noise ratio, a long time span and a nearly continuous duty-cycle.
Aims: We analyse the light-curves of four bright targets observed in the seismology field and study short-lived small spots in solar-like stars.
Methods: We present …
The Largest Gravitational Lens: MACS J0717.5+3745 (z = 0.546)
Broadhurst, Tom; Zitrin, Adi; Rephaeli, Yoel +1 more
We identify 13 sets of multiply-lensed galaxies around MACS J0717.5+3745 (z = 0.546), outlining a very large tangential critical curve of major axis ~2farcm8, filling the field of the Hubble Space Telescope/Advanced Camera for Surveys. The equivalent circular Einstein radius is θ e = 55'' ± 3'' (at an estimated source redshift of z