The Depths of the Universe

100-inch telescope 61 Cygni absolute brightness apparent brightness appear astronomer Barnard's dark nebula Barnard's photograph bright nebula Bruce telescope camera centre components cycle Dark markings detected diameter direction of whirl discovery disk distance dust dwarf star earth electric electrons Ellerman exposure Faraday Faraday's field in Auriga Fresnel rhomb Galileo giant star glass globular clusters Globular star cluster heavens hemisphere Herschel Hooker telescope hydrogen vortices inches Jupiter laboratory law of sun-spot lens light light-years lines of force magnetic field magnitude measure Milky Mount Wilson Observatory Nebula in Orion Nicol prism objects obscuring masses observations opposite polarity parallax particles phenomena Photographed by Barnard plate poles region relative intensities reversal rotation Shapley Showing stars shown slit solar activity solar atmosphere space spectrograph spectroheliograph spectroscope spectrum spot vortex star clouds star cluster Star field STELLAR DISTANCE stellar universe sun's terrestrial tion tower telescope visible Yerkes Yerkes telescope Zeeman Zeeman effect