Outlines of Astronomy, Part 2

61 Cygni action amount angle angular aphelion appear astronomers attraction average axis bright calculation Centauri centre coincidence comet conjunction considerable curve Cygni described diameter difference direction distance disturbed body disturbed orbit disturbing force Ditto double stars earth effect elements elliptic epoch equal equator excentricity fixed force acting greater heavens Hind inclination increase inequality instance interval Julian Julian period Jupiter length less light line of apsides longitude lunar magnitude mass mean motion meteors minute momentary moon moon's nearly nebula node normal force nucleus nutation observed Orionis P's orbit parallax perigee perihelion perihelion passage period perturbations planetary portion precisely produced proper motion quadratures recede recess regarded remarkable respect result retrograde revolution round Saturn seen semiaxis sidereal sidereal day situation solar solar apex sun's supposed surface syzygies tail tangential force telescopes tion tricity turbing Uranus variation velocity visible whole