Cosmos: A Sketch of a Physical Description of the Universe, Volume 3

1st magnitude 61 Cygni 6th magnitude according Aldebaran Annuaire appeared Arago Aratus Arcturus Argelander Aristot Astr Astron astronomers atmosphere Bessel brightness Cape Cassiopeia catalogue celestial centre century Ceti colour comets Compare conjecture constellations cosmical bodies Cosmos Cygni d'une Decl determined diameter discovery distance double stars earth ether étoiles fainter fixed stars Greek Hipparchus Hist instruments intensity of light Jacques Cassini Jupiter Kepler l'image l'œil lumière luminous lunette Lyræ Mädler ment Milky moon Nachr naked eye nature nebula number of stars object-glass observations Ophiuchus optical orbits Orionis parallax period phenomena Philos photometric physical planetary planets portion proper motion Ptolemy quæ radiation rayons rays reference refraction regions of space remarkable result right ascension satellites scintillation seen Sir John Herschel Sirius solar system southern hemisphere sphere stellar strata Struve surface telescope terrestrial tion Tycho Brahe Ursæ variable stars vault of heaven velocity visible vision