Outlines of Astronomy

action actual advance amount angle angular appear arise ascertained astronomical attraction axis becomes body bright calculation called cause centre circle comet compared complete considerable considered continually corrected corresponding course described determined diameter difference direction distance disturbing earth ecliptic Edition effect elements ellipse equal equator error evident exact excentricity existence fact figure fixed follows force former give given greater heavens History horizon inclination increase interval known latter least length less light longitude magnitude mass mean measure meridian minute moon motion nature nearly node object observed opposite orbit parallel passing period planet pole portion position precisely present produced proportion reason referred regarded remain remarkable represented respect result round seen side sidereal situation solar space sphere stars station successive sun's suppose surface telescope tion true variation visible vols whole