Micrometer Measures of Double Stars Micrometer measures of 795 double stars made with the 26 inch (0.66 m)refractor of the US Naval Observatory from 1984 to 1990 are presented.
ICCD speckle observations of binary stars. IV - Measurements during 1986-1988 from the Kitt Peak 4 M telescope One thousand five hundred and fifty measurements of 1006 binary starsystems observed mostly during 1986 through mid-1988 by means of speckleinterferometry with the KPNO 4-m telescope are presented. Twenty-onesystems are directly resolved for the first time, including newcomponents to the cool supergiant Alpha Her A and the Pleiades shellstar Pleione. A continuing survey of The Bright Star Catalogue yieldedeight new binaries from 293 bright stars observed. Corrections tospeckle measures from the GSU/CHARA ICCD speckle camera previouslypublished are presented and discussed.
Interstellar extinction and the composition of dust grains A model for interstellar dust is proposed based on recent laboratorydata on the properties of amorphous carbon and silicate materials. It issuggested that the wavelength dependence of interstellar extinction aswell as many other properties of interstellar dust can be explained by amodel in which small hydrated silicate particles are coated with a thinlayer of amorphous carbon. It is speculated that such layers are thinenough to exhibit quasi-quantum character.
