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ISO observations of Wolf-Rayet galaxy Haro 3.
Hanlon, L.; McBreen, B.; Clavel, J. +9 more
Observations of the blue compact dwarf galaxy Haro 3 have been obtained with the ISOCAM and ISOPHOT instruments on the Infrared Space Observatory (ISO). The PHT-S spectrum (6-12µm) is dominated by four emission bands that are frequently attributed to polycyclic aromatic hydrocarbons (PAHs) and strong SIV emission. Two CAM filters, LW6 (7-8.5…
ULYSSES at high heliographic latitudes: an introduction.
Smith, E. J.; Cooper, J. F.; Marsden, R. G. +1 more
The unique in situ observations acquired by the scientific instrumentation on board the Ulysses spacecraft have provided, for the first time, a comprehensive, 3-dimensional view of the heliosphere from the solar equator to the poles near solar minimum. Since beginning its journey out of the ecliptic plane in February, 1992, Ulysses has acquired a …
Seyfert Galaxies. IV. Nuclear Profiles of Markarian Seyfert Galaxies from Hubble Space Telescope Images
MacKenty, John W.; Griffiths, Richard E.; Nelson, Charles H. +1 more
We have examined the nuclear profiles of the Seyfert and non-Seyfert Markarian galaxies in our near-infrared Hubble Space Telescope WF/PC-1 snapshot survey. We find that nuclei of types 1-1.5 Seyfert galaxies are dominated by strong point sources, while those of Seyfert 2 and non- Seyfert Markarian galaxies tend to be resolved, less distinguished,…
Compact radio structure in the Seyfert nucleus of NGC 5929.
Muxlow, T. W. B.; Steffen, W.; Kukula, M. J. +4 more
The authors present MERLIN and VLA radio measurements of the Seyfert galaxy NGC 5929 at 15, 8, 5, 1.6 and 0.4 GHz. All measurements have subarcsecond angular resolution ranging from 0.6 arcsec at 0.4 GHz to 50 mas at 5 GHz. The authors confirm the triple structure reported in earlier studies. The weak central source of the triplet is almost certai…
The Ultraviolet/Optical Continuum of Hercules X-1/HZ Herculis
Cheng, F. H.; Vrtilek, S. D.
We present observations of the binary X-ray pulsar system Hercules X-1/HZ Herculis taken with the International Ultraviolet Explorer (lUE) and several ground-based observatories as part of a multi- wavelength campaign conducted in 1993 August. The 1993 campaign found the source in an unusual state, with substantially reduced X-ray flux, and also r…
Nova V351 Puppis 1991: a multiwavelength study of the nebular phase
Sonneborn, G.; Saizar, P.; Shore, S. N. +4 more
We combine ground-based optical and IUE spectrophotometry to study the physical conditions in the shell of Nova V351 Puppis 1991. The structure and the evolution of the shell during the early nebular (i.e. optically thin) phase are discussed in this paper. The reddening, derived from recombination lines, is E(B-V)=0.72+/-0.10. The optical/UV light…
The Wolf-Rayet Star HD 197406, with Its Strongly Ionizing Close Companion
Moffat, Anthony F. J.; Marchenko, Sergey V.; Tovmassian, Gaghik H. +1 more
High-quality, phase-dependent CCD spectra are presented for the first time for this unusual Population I, runaway WN7 single-line binary system. Besides confirming a previous orbit based on the N iv 4058 Å emission line, these spectroscopic data show phase-dependent, line-profile variations, especially in He II. The low mass function, but normal o…
Complex Gaseous Structure in the Nucleus of NGC 5252
Wilson, Andrew S.; Morse, Jon A.; Tsvetanov, Zlatan I. +1 more
We present several Hubble Space Telescope (HST) WFPC2 emission-;ine and continuum images of NGC 5252, a Seyfert 2 50 galaxy with a large-scale "ionization bi-cone." In the Hα + [N II] image, the nucleus is bracketed at 0"3 radii by two bright emission-line clumps along P.A. = 35° (∼20° from the major axis of the large-scale stellar disk). These th…
ISOCAM observations of NGC 6946: Mid-IR structure.
Helou, G.; Lord, S. D.; Malhotra, S. +12 more
The nearby spiral galaxy NGC 6946 was observed with ISO-CAM in the mid-infrared, achieving 7" resolution and sub-MJy/sr sensitivity. Images taken with CAM filters LW2 (7µm) and LW3 (15µm) are analysed to determine the morphology of this galaxy and understand better the emission mechanisms. The mid-infrared emission follows an exponenti…
Comparison of Galileo Probe and Earth-Based Translation Rates of Jupiter's Equatorial Clouds
Simon, Amy A.; Beebe, Reta F.; Huber, Lyle F.
The Doppler wind speeds derived from Galileo probe data are comparable with the maximum translation speeds observed in the equatorial zone by Voyager 1 and the Hubble Space Telescope. Slower published values of east-west winds are based on measurements of larger features and should be interpreted as translation rates of large weather systems inter…