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Hubble Space Telescope observations of the nucleus fragment 73P/Schwassmann Wachmann 3-C
Lamy, P.; Toth, I.; Weaver, H. A.
The investigation of fragmented comets provides information on the physical properties and internal structure of cometary nuclei, as well as insights into the mechanisms responsible for cometary breakups. The Jupiter-family Comet 73P/Schwassmann-Wachmann 3 (73P/SW3) fragmented non-tidally into at least four components, and probably more, in the au…
Fe VII lines in the spectrum of RR Telescopii
Young, P. R.; Lobel, A.; Berrington, K. A.
Thirteen transitions within the ground 3d2 configuration of Fe vii are identified in ultraviolet and optical spectra of the symbiotic star RR Telescopii obtained with the STIS instrument of the Hubble Space Telescope. The line fluxes are compared with theoretical data computed with the recent atomic data of Berrington et al., and high r…
An update on the ring exosphere and plasma disc of Saturn
Ip, W. -H.
A re-examination of the mass budget of the ring exosphere of Saturn - as prompted by the most recent Cassini measurements in the vicinity of the ring system - indicates that the corresponding number density could reach the level of 2-3 × 105 cm-3 at maximum. Such extended exospheric structure in equilibrium with a thin ring p…
Complex geology of two large impact craters in Tyrrhena Terra, Mars: Detailed analysis using MEX HRSC camera data
Neukum, G.; Korteniemi, J.; Kostama, V. -P. +5 more
Tyrrhena Terra, located just north of the roughly 200 km Hellas impact basin, is a typical region of the ancient cratered southern highlands on Mars. Its base material is a mixture of Hellas ejecta, prebasin remnants, and highland terrain, all later saturated with smaller (<200 km) impact craters. Fluvial and lacustrine deposits, erosion, tecto…
Multipoint Observations of Ionic Structures in the Plasmasphere by CLUSTER-CIS and Comparisons With IMAGE-EUV Observations and With Model Simulations
Parks, George K.; Dandouras, Iannis; Vallat, Claire +12 more
The 4 Cluster spacecraft orbit the Earth in a highly eccentric polar orbit at 4 RE perigee, and this permits them to sample the ring current, the radiation belts and the outer plasmasphere. Data provided by the Cluster Ion Spectrometry (CIS) instruments are used to analyze Cluster crossings of the plasmasphere. CIS is capable of obtaini…
Chandra and XMM-Newton Observations of the Exceptional Pulsar B0628-28
Ögelman, H.; Tepedelenlıoǧlu, E.
PSR B0628-28 is a radio pulsar that was first detected in the X-ray band by ROSAT and then later observed with Chandra and XMM-Newton. The Chandra observation yielded an X-ray luminosity 2 orders of magnitude higher than what is expected for spin-powered pulsars; also, there were no pulsations detected. The XMM-Newton observation, however, reveals…
Modeling Solar Oscillation Power Spectra. I. Adaptive Response Function for Doppler Velocity Measurements
Jefferies, Stuart M.; Vorontsov, Sergei V.
Improving the accuracy and resolution of helioseismic inversions calls for more accurate modeling of the observational p-mode power spectra from which the solar oscillation frequencies are traditionally measured. We present a new technique of calculating the response function (leakage matrix) for Doppler velocity measurements that is based largely…
Diffuse Component Spectra of Solar Active Regions at Submillimeter Wavelengths
Silva, Adriana V. R.; Kaufmann, Pierre; Levato, Hugo +4 more
Solar maps at 212 and 405 GHz obtained by the Solar Submillimetric Telescope (SST) show regions of enhanced brightness temperature, which coincide with the location of active regions. A statistical study of the radio emission from these active regions was performed for the first time at such high frequencies during 23 days on June and July 2002, w…
Host Galaxies of High-Redshift Active Galactic Nuclei in the Great Observatories Origins Deep Surveys Fields
Akiyama, Masayuki
The star formation rates and the stellar masses of the host galaxies of active galactic nuclei (AGNs) at high redshifts are key to understanding the evolution of the relation between the mass of the spheroidal component of a galaxy and the mass of its central black hole (Mbulge-M• relation). We investigate the host galaxies o…
OH Rotational Lines as a Diagnostic of the Warm Neutral Gas in Galaxies
Cernicharo, José; Goicoechea, Javier R.; Martín-Pintado, Jesus
We present Infrared Space Observatory (ISO) observations of several OH, CH, and H2O rotational lines toward the bright infrared galaxies NGC 253 and NGC 1068. As found in the Galactic clouds in Sgr B2 and Orion, the extragalactic far-IR OH lines change from absorption to emission depending on the physical conditions and distribution of …