Outlines of AstronomyLongman, Brown, Green, Longmans, 1851 - 661 стор. |
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Сторінка 122
... disc be formed , and cemented on a circular plate of parallel glass , or otherwise sustained , close to and concentric with the other by a framework of metal so light as to intercept but a small portion of the light which passes on the ...
... disc be formed , and cemented on a circular plate of parallel glass , or otherwise sustained , close to and concentric with the other by a framework of metal so light as to intercept but a small portion of the light which passes on the ...
Сторінка 123
... disc on the other , will arise . Now , let this combination be applied at such a point of the cone of rays , between the object - glass and its focus , that the discs shall occupy exactly half the area of its section . Then will half ...
... disc on the other , will arise . Now , let this combination be applied at such a point of the cone of rays , between the object - glass and its focus , that the discs shall occupy exactly half the area of its section . Then will half ...
Сторінка 206
... disc takes to traverse the meridian in the transit instrument . The greatest apparent diameter corre- sponds to the 1st of December , or to the greatest angular velocity , and measures 32 ′ 35 ′′ -6 , the least is 31 ′ 31 ′′ -0 ; and ...
... disc takes to traverse the meridian in the transit instrument . The greatest apparent diameter corre- sponds to the 1st of December , or to the greatest angular velocity , and measures 32 ′ 35 ′′ -6 , the least is 31 ′ 31 ′′ -0 ; and ...
Сторінка 228
... disc to 461 miles ; and a circle of this diameter ( containing therefore nearly 167000 square miles ) is the least space which can be distinctly discerned on the sun as a visible area . Spots have been observed , however , whose linear ...
... disc to 461 miles ; and a circle of this diameter ( containing therefore nearly 167000 square miles ) is the least space which can be distinctly discerned on the sun as a visible area . Spots have been observed , however , whose linear ...
Сторінка 229
... disc , and their ap- pearance is as represented in Plate I. fig . 1 . ( 389. ) But what are the spots ? Many fanciful notions have been broached on this subject , but only one seems to have any degree of physical probability , viz ...
... disc , and their ap- pearance is as represented in Plate I. fig . 1 . ( 389. ) But what are the spots ? Many fanciful notions have been broached on this subject , but only one seems to have any degree of physical probability , viz ...
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Outlines of Astronomy John Frederick William Herschel,Sir John Frederick William Herschel Повний перегляд - 1851 |
Загальні терміни та фрази
angle angular appear apsides ascertained astronomical axis bright calculation celestial centre circle comet curve described diameter difference direction disc distance disturbed body disturbing force diurnal diurnal motion double stars earth ecliptic Edition effect elements ellipse epoch equal equator equinoctial equinox error exact excentricity fixed globe heavens heliocentric horizon inclination inequality instance instrument interval Jupiter latitude latter less light longitude lunar magnitude mass mean measure meridian moon moon's motion nearly nebula node normal force nutation object observed orbit parallax parallel perigee perihelion period perturbations planet planetary pole portion position Post 8vo precession proper motions proportion recede recess reckoned refraction respect result revolution right ascension rotation round satellites Saturn seen sidereal sidereal day sidereal period situation solar sphere spherical stars station sun's suppose surface syzygies tangential force telescope tion Uranus variation velocity visible vols whole Woodcuts zenith
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Сторінка 674 - A Dictionary of Science, Literature, and Art : Comprising the History, Description, and Scientific Principles of every Branch of Human Knowledge ; with the Derivation and Definition of all the Terms in General Use. Edited by WT BRANDE, FRSL and E.