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Water in Space: The Water World of ISO
Cernicharo, José; Crovisier, Jacques
In this review we present the main results obtained by the ISO satellite on the abundance and spatial distribution of water vapor in the direction of molecular clouds, evolved stars, galaxies, and in the bodies of our Solar System. We also discuss the modeling of H2O and the difficulties found in the interpretation of the data, the need…
Catastrophic Cooling of Impulsively Heated Coronal Loops
Erdélyi, Robert; Mendoza-Briceño, César A.; Sigalotti, Leonardo Di G.
The physical mechanisms that cause the heating of the solar corona are still far from being completely understood. However, recent highly resolved observations with the current solar missions have shown clear evidence of frequent and very localized heating events near the chromosphere that may be responsible for the observable high temperatures of…
Stellar Cluster Fiducial Sequences with the Advanced Camera for Surveys
Ferguson, Henry C.; Brown, Thomas M.; Rich, R. Michael +6 more
We present color-magnitude diagrams of five Galactic globular clusters and one Galactic open cluster spanning a wide range of metallicity (-2.1<~[Fe/H]<~+0.3), as observed in the F606W (broad V) and F814W (I) bands with the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope. These clusters are part of two large ACS programs meas…
Uranus in 2003: Zonal winds, banded structure, and discrete features
Hammel, H. B.; de Pater, I.; Gibbard, S. +2 more
Imaging of Uranus in 2003 with the Keck 10-m telescope reveals banded zonal structure and dozens of discrete cloud features at J and H bands; several features in the northern hemisphere are also detectable at K'. By tracking features over four days, we extend the zonal wind profile well into the northern hemisphere. We report the first measurement…
Radio and X-Ray Signatures of Magnetic Reconnection behind an Ejected Flux Rope
Pick, M.; Krucker, S.; Démoulin, P. +2 more
We present a detailed study of a complex solar event observed on 2002 June 2. Joint imaging EUV, X-ray, and multiwavelength radio observations allow us to trace the development of the magnetic structure involved in this solar event up to a radial distance of the order of 2 Rsolar. The event involves type II, III, and IV bursts. The type…
Statistical Properties Of Sunspots In 1996 2004: I. Detection, North South Asymmetry And Area Distribution
Zharkova, V. V.; Zharkov, S.; Ipson, S. S.
The first statistical results in sunspot distributions in 1996-2004 obtained from the Solar Feature Catalogues (SFC) are presented. A novel robust technique is developed for automated identification of sunspots on SOHO/MDI white-light (WL) full-disk solar images. The technique applies image standardization procedures for elimination of the limb da…
Systematic uncertainties in the analysis of star cluster parameters based on broad-band imaging observations
Bastian, N.; de Grijs, R.; Anders, P. +5 more
High-resolution Hubble Space Telescope (HST) imaging observations of star cluster systems provide a very interesting and useful alternative to spectroscopic studies for stellar population analyses with 8-m class telescopes. Here, we assess the systematic uncertainties in (young) cluster age, mass and (to a lesser extent) extinction and metallicity…
Limits from the Hubble Space Telescope on a Point Source in SN 1987A
Filippenko, Alexei V.; Garnavich, Peter; Fransson, Claes +16 more
We observed supernova 1987A (SN 1987A) with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope (HST) in 1999 September and again with the Advanced Camera for Surveys (ACS) on the HST in 2003 November. Our spectral observations cover ultraviolet (UV) and optical wavelengths from 1140 to 10266 Å, and our imaging observatio…
First results of low frequency electromagnetic wave detector of TC-2/Double Star program
Zhou, L.; Santolík, O.; Parrot, M. +17 more
LFEW is a low frequency electromagnetic wave detector mounted on TC-2, which can measure the magnetic fluctuation of low frequency electromagnetic waves. The frequency range is 8 Hz to 10 kHz. LFEW comprises a boom-mounted, three-axis search coil magnetometer, a preamplifier and an electronics box that houses a Digital Spectrum Analyzer. LFEW was …
Cassini observations of the thermal plasma in the vicinity of Saturn's main rings and the F and G rings
Gurnett, D. A.; Coates, A. J.; Thomsen, M. F. +10 more
The ion mass spectrometer on Cassini detected enhanced ion flux near Saturn's main rings that is consistent with the presence of atomic and molecular oxygen ions in the thermal plasma. The ring ``atmosphere'' and ``ionosphere'' are likely produced by UV photosputtering of the icy rings and subsequent photoionization of O2. The identific…