Manual of astronomyLippincott, 1853 - 331 páginas |
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Página 9
... whole surface , as well as from other reasons which have presented themselves to laborious investi- gators ; it has been concluded that the spots arise from variations in the luminous atmosphere of the sun , and that the nuclei are ...
... whole surface , as well as from other reasons which have presented themselves to laborious investi- gators ; it has been concluded that the spots arise from variations in the luminous atmosphere of the sun , and that the nuclei are ...
Página 10
... the angle bca , is equal to the arc E D , which measures the angle E a D , or the portion of the earth's orbit which she has passed over in that time ; hence , As 360 ° + ba , the whole space described 10 DESCRIPTIVE ASTRONOMY .
... the angle bca , is equal to the arc E D , which measures the angle E a D , or the portion of the earth's orbit which she has passed over in that time ; hence , As 360 ° + ba , the whole space described 10 DESCRIPTIVE ASTRONOMY .
Página 11
John Drew. As 360 ° + ba , the whole space described by the spot the whole time elapsed between the two dis- appearances : 360 ° the true time of the revolution of the sun on his axis , as it would have appeared to the earth had it been ...
John Drew. As 360 ° + ba , the whole space described by the spot the whole time elapsed between the two dis- appearances : 360 ° the true time of the revolution of the sun on his axis , as it would have appeared to the earth had it been ...
Página 13
... whole , E 8 Fig . 3 . P let us suppose the diameter of the sun to measure 32 ' ; make Eo 64 equal parts ; when a quarter of the year has expired , let the diameter of the sun be measured , and , on the supposition of its being 311⁄2 ...
... whole , E 8 Fig . 3 . P let us suppose the diameter of the sun to measure 32 ' ; make Eo 64 equal parts ; when a quarter of the year has expired , let the diameter of the sun be measured , and , on the supposition of its being 311⁄2 ...
Página 19
... whole of her at once . The surface of the water , then , which we are apt to think perfectly level , is not so ; and hence , in construct- ing canals , an allowance of eight inches in a mile , below the horizontal plane , is necessary ...
... whole of her at once . The surface of the water , then , which we are apt to think perfectly level , is not so ; and hence , in construct- ing canals , an allowance of eight inches in a mile , below the horizontal plane , is necessary ...
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Términos y frases comunes
achromatic altitude angle appear ascer astronomers atmosphere attraction axis azimuth calculated celestial globe circle collimation comet correct declination density describe determine diameter difference direction disc diurnal double stars earth earth's orbit east ecliptic equal equator equatorial equinoctial error fixed stars force Greenwich heavenly body heavens Herschel horizon hour-angle hour-circle inches inclination inferior planet instrument Jupiter latitude length light longitude Mars mean measured Mercury meridian miles minutes moon moon's motion Nautical Almanac nebula nodes object object-glass observation Observatory parallax pass pendulum perihelion perpendicular planet planetary Plate point of Aries polar distance pole portion position proportion rays refraction revolution revolve round right ascension round the sun satellites Saturn seconds seen shadow shew shewn side sidereal sidereal day space sphere spherical sun's superior planet suppose surface telescope tion transit transit circle Uranus Venus vertical vibration wire
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Página 131 - Milky-way, when exploring that region with his best glasses, he has had fields of view which contained no less than 588 stars, and these were continued for many minutes; so that " in one quarter of an hour's time there passed no less than one hundred and sixteen thousand stars through the field of view of his telescope.
Página 42 - ... posterity; but the record remains, and transfuses all its own exactness into every determination which takes it for a groundwork, giving to inferior instruments — nay, even to temporary contrivances, and to the observations of a few weeks or days — all the precision attained originally at the cost of so much time, labour, and expense.
Página 178 - That the interval between the orbits of any two planets is about twice as great as the inferior interval, and only half the superior one.
Página 11 - ... it is most probably also inhabited, like the rest of the planets, by beings whose organs are adapted to the peculiar circumstances of that vast globe.
Página 1 - And yet, fair bow, no fabling dreams But words of the Most High, Have told why first thy robe of beams Was woven in the sky.
Página 42 - The stars are the landmarks of the universe ; and, amidst the endless and complicated fluctuations of our system, seem placed by its Creator as guides and records, not merely to elevate our minds by the contemplation of what is vast, but to teach us to direct our actions by reference to what is immutable in his works.
Página 180 - A plane rectilineal angle is the inclination of two straight lines to one another, which meet together, but are not in the same straight line.
Página 42 - ... and in all places, of a delicacy so extreme as to be a test for every instrument yet invented by man, yet equally adapted for the most ordinary purposes; as available for regulating a town clock as for conducting a navy to the Indies ; as effective for mapping down the intricacies of a petty barony as for adjusting the boundaries of Transatlantic empires. When once its place has been thoroughly ascertained and carefully recorded, the brazen circle with which...