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Ultraviolet Observations of the Symbiotic Star AS 296

Feibelman, W. A.; Moreno, H.; Gutierrez-Moreno, A.

AS 296 is a well-known S-type symbiotic star which underwent an optical outburst during 1988. In this paper, UV data based on IUE observations obtained both during the quiescent and outburst stages are presented and discussed, correlating them to observations made in the optical region. It is concluded that the object is a symbiotic nova, in which…

Properties of the SN 1987A Circumstellar Ring and the Distance to the Large Magellanic Cloud: Erratum

Panagia, N.; Kirshner, R. P.; Macchetto, F. +2 more

Figures 2 and 3 of the Letter "Properties of the SN 1987A Circumstellar Ring and the Distance to the Large Magellanic Cloud," by N. Panagia, R. Gilmozzi, F. Macchetto, H.-M. Adorf, and R. P. Kirshner (ApJ, 380, L23 [1991]), contained some errors; i.e., Figure 2 had the wrong theoretical curve as a fit to the time evolution of the C III)λ1909 line …

Diffusive shock acceleration and the March 1991 solar events

Krupp, N.; Keppler, E.; Korth, A. +7 more

Spectral and anisotropy measurements are reported for protons between 0.5 and 1.4 MeV during the particle increases associated with the passage of 3 interplanetary shocks past Ulysses between March 19 and March 31 1991. The data are interpreted in terms of diifusive shock acceleration in the travelling solar induced disturbances to the solar plasm…

Seyfert Galaxy Ultraviolet Emission-Line Intensities and Variability: A Self-consistent Photoionization Analysis Applied to Broad-Line--emitting Gas in NGC 3783

Koratkar, Anuradha P.; MacAlpine, Gordon M.

Both strong and weak ultraviolet emission lines in SeYfert 1 galaxies have been accurately measured from reextracted short-wavelength camera data in the IUE satellite data archives. Line ratios, equivalent widths, and trends as functions of continuum variability were used to constrain numerical modeling parameters in detailed photoionization analy…

The Ultraviolet Spectrum of HH 24A and its Relation to Optical Spectra

Noriega-Crespo, A.; Brugel, E. W.; Boehm, K. H. +1 more

We have studied the spectrum of the brightest part (HH 24A) of the complex Herbig-Haro object HH 24 in the short wavelength (1300 A The ultraviolet spectrum is definitely detected in three observations with exposure times of 560 to 680 min. It is, however, sufficiently faint that corrections for the IUE "artifact spectrum" (as described by Crensha…

Almucantar deformations in the method of equal altitudes

Pesek, I.

Systematic deformations of apparent almucantar of order of 0.1 arcsec were derived from two five-year series of circumzenithal observations by the method of equal altitudes. Simple method is presented which makes it possible to check for almucantar deformation all data obtained by the method of equal altitudes, selected for rereducing earth rotati…

Geminga pulsar in COS-B and HEAO-B observations.

Sun, X.; Ma, Y.; Li, T. +4 more

The Billion Amp Current that Flows Round Jupiter

Henbest, N.

UV observations of LB 3193 and LB 3116 : two hot post-AGB object in the galactic halo ?

Lamers, H. J. G. L. M.; Quin, D. A.

LB 3193 and LB 3116 have visual spectra indicating that they are B2-B5 supergiants situated at large distances from the galactic plane. UV observations of both objects show that they are metal deficient stars, whose energy distributions match their adopted atmospheric parameters. Further investigation of mass luminosity relationships of various ev…

HST observations of the inner coma of Comet Levy 1990c.

Pasian, F.; Fulle, M.; Benvenuti, P.

Comet Levy 1990c was observed by the Hubble Space Telescope on 27 September 1990, thus allowing to test data reduction procedures which will allow to model the nucleus of future targets of cometary space missions. The authors observe faint hemispherical shells expanding in the coma, which is structured as a sunward fan deflected by solar radiation…