Practical Astronomy and Geodesy: including the projections of the Sphere and Spherical Trigonometry

aberration altitude angular distance apparent ascension and declination astronomical axis azimuth bisected celestial body celestial sphere centre circle colatitude computed considered correction corresponding cotan degrees described determined diameter difference disk earth ecliptic ellipse equal equator equatorial equinoctial point error expressed fixed star formula given Greenwich heliocentric horary horizontal parallax hour angle instant instrument interval latitude latter let fall mean meridian micrometer moon moon's motion movement Nautical Almanac nearly node noon nutation obliquity observed obtained P'PR parallax parallel perihelion perpendicular plane passing polar distance pole position projection radius vector refraction represented revolution revolve right angles right ascension satellite screw sector semidiameter sidereal sidereal clock sine solar sphere spherical triangle star's station subtracted sun's supposed surface tangent telescope transit transit telescope Trigon variation vertical wire zenith distance zero