What people are saying - Write a review
We haven't found any reviews in the usual places.
Other editions - View all
Elements of Astronomy with Numerous Examples and Examination Papers
George W Parker
No preview available - 2016
aberration angle subtended angular distance annual parallax apparent diameter axis calculate called celestial equator celestial pole celestial sphere centre circular clock coincide colat comets complete revolution corresponding crosses the meridian determined direction disc diurnal motion Dublin earth's orbit ecliptic equal equator equinox error fixed stars greatest Greenwich heavenly bodies heavens Hence horizon horizontal parallax inferior conjunction inferior planet interval Jupiter known latitude light line of collimation longitude lunar eclipse Mars mean noon mean solar mean sun measured Mercury meridian altitude method miles moon's moon’s move Nautical Almanac nearly node observer opposite parallax parallel perpendicular point of Aries position precession radius rays refraction represent revolve round right angles right ascension rotation round the sun satellites seen shadow sidereal hours solstice spider line sun’s superior planet surface synodic period telescope transit twilight velocity Venus vertical zenith distance
Page 182 - The greatest number of eclipses that can happen in a year is seven; five of the sun and two of the moon, or four of the sun and three of the moon. The least number is two, both of which must be of the sun.
Page 53 - When a ray passes from a rarer to a denser medium, it is refracted or bent towards the perpendicular ; when a ray of light passes from a denser to a rarer medium...
Page 173 - An eclipse of the sun is caused by the interposition of the moon between the earth and...
Page 169 - ... moon. If the plane of the moon's orbit coincided with the plane of the ecliptic, there would be an eclipse at every...
Page 89 - The radius vector drawn from the sun to a planet sweeps out equal areas in equal times.
Page 80 - ... orbits of all the planets, except Pallas, to the plane of the earth's orbit are small. The method of ascertaining the inclinations will be afterward shewn. The points, in which a planet's orbit intersects the plane of the earth's orbit, are called nodes. The node through which the planet passes from the southern to the northern side of the ecliptic, is called the ascending node, and the other the descending node. When an inferior planet is near one of its nodes at inferior conjunction, it appears...
Page 65 - The orbit of each planet is an ellipse, having the sun in one of its foci. II. The radius vector joining the sun to the planet sweeps over equal areas in equal times. III. The squares of the periodie times of the several planets vary as the cubes of their mean distances from the sun.
Page 20 - The Latitude of a place is its distance north or south of the equator, measured on the meridian.