Elements of Astronomy with Numerous Examples and Examination PapersLongmans, Green & Company, 1902 - 233 pages |
From inside the book
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Page vii
... Transit Instrument . Various Errors .nd Adjustments . The Meridian Circle . Regulation of the Clock . Equatorial and Micrometer . Alt- Azimuth Instrument , · CHAPTER IV . ATMOSPHERIC REFRACTION . Effect on the Apparent Position of a ...
... Transit Instrument . Various Errors .nd Adjustments . The Meridian Circle . Regulation of the Clock . Equatorial and Micrometer . Alt- Azimuth Instrument , · CHAPTER IV . ATMOSPHERIC REFRACTION . Effect on the Apparent Position of a ...
Page 33
... transit occurs . Definition . — The sidereal time at any instant is the interval that has elapsed since the preceding transit of the first point of Aries expressed in sidereal hours , minutes , & c . As the right ascensions of heavenly ...
... transit occurs . Definition . — The sidereal time at any instant is the interval that has elapsed since the preceding transit of the first point of Aries expressed in sidereal hours , minutes , & c . As the right ascensions of heavenly ...
Page 34
... Transit Instrument . 26. The object of this instrument is to determine the exact instant at which a body crosses the meridian . It consists of a telescope rigidly fixed to a horizontal axis . At the extremities of this horizontal axis ...
... Transit Instrument . 26. The object of this instrument is to determine the exact instant at which a body crosses the meridian . It consists of a telescope rigidly fixed to a horizontal axis . At the extremities of this horizontal axis ...
Page 35
... transit over one line , the seven are used in order that the observer may note the time at which the image crosses each of them , when the mean of these being taken will , in all probability , give a more accurate result than one ...
... transit over one line , the seven are used in order that the observer may note the time at which the image crosses each of them , when the mean of these being taken will , in all probability , give a more accurate result than one ...
Page 36
... transit instrument , to be perfectly adjusted , must satisfy the three following conditions : - ( 1 ) The line of collimation should be perpendicular to the axis of rotation of the telescope . ( 2 ) The axis of rotation should be ...
... transit instrument , to be perfectly adjusted , must satisfy the three following conditions : - ( 1 ) The line of collimation should be perpendicular to the axis of rotation of the telescope . ( 2 ) The axis of rotation should be ...
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Elements of Astronomy with Numerous Examples and Examination Papers George W Parker No preview available - 2016 |
Common terms and phrases
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 moon's move Nautical Almanac nearly node observer opposite parallax parallel pendulum 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 declination superior planet surface synodic period telescope transit twilight velocity Venus vertical zenith distance
Popular passages
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 227 - Ocean, the first thing which strikes us is, that, the north-east and south-east monsoons, which are found the one on the north and the other on...
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.
Page 184 - The mean sun is an imaginary sun which moves to the eastward in the equinoctial at a uniform rate equal to the average rate of the true sun in the ecliptic.