Distance Determination of Variable Galactic Sources

We have developed a timing analysis method to determine the distances of variable galactic X-ray sources based on the method advanced by Tr\"{u}mper and Sch\"{o}nfelder in 1973. The light-curve of the halo produced by the scattering of X-rays off the interstellar dust is delayed and smeared by the dust grains. This method utilizes the differences between the power density spectra of the point source and the halo. We present the details of this method and our first applications of this method to the Chandra data of X-ray binary Cyg X-3.Comment: 5 page and 3 figure, The 6th pacific rim conference on steller astrophysics -- a tribute to Helmut A. Ab

IUE OBSERVATIONS OF EXTRA-GALACTIC OBJECTS

During the commissioning phase of IUE several extragalactic objects were observed spectrally at low dispersion in the UV range λλ1150–3200: the Seyfert galaxies NGC4151 and NGC1068, the QSO 3C273, the BL Lacertae object B2 1101 +38, the giant elliptical galaxy M87 and the spiral galaxy M81. The results obtained are presented and a preliminary analysis given for all six objects, discussing the continuous spectrum, extinction, emission line spectrum and absorption line spectrum, where possible for each case. Several new or confirmatory astrophysical results are obtained