History of Astronomy |
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Page 107
... parallax of Mars in opposition , and found the sun's distance 93,080,000 miles . He con- sidered that , while the superiority of the heli- ometer had been proved , the results would be still better with the points of light shown by ...
... parallax of Mars in opposition , and found the sun's distance 93,080,000 miles . He con- sidered that , while the superiority of the heli- ometer had been proved , the results would be still better with the points of light shown by ...
Page 109
... parallax of the sun is the angle subtended by the earth's radius at the sun's distance . 44 2 A. R. Hinks , R.A.S .; Monthly Notices , June , 1909 . In the Encyclopædia Britannica , article Tele- scope , " and in Grant's Physical ...
... parallax of the sun is the angle subtended by the earth's radius at the sun's distance . 44 2 A. R. Hinks , R.A.S .; Monthly Notices , June , 1909 . In the Encyclopædia Britannica , article Tele- scope , " and in Grant's Physical ...
Page 161
... parallax failed , but led to the discovery of aberration , nutation , and the true velocity of light . Parallax . The absence of stellar parallax was the great objection to any theory of the earth's motion prior to Kepler's time . It is ...
... parallax failed , but led to the discovery of aberration , nutation , and the true velocity of light . Parallax . The absence of stellar parallax was the great objection to any theory of the earth's motion prior to Kepler's time . It is ...
Page 162
... parallax 1 " .16 . His successor at the Cape , Maclear , reduced this to o " .92 . In 1835 Struve assigned a doubtful parallax of o " .261 to Vega ( a Lyræ ) . But Bessel's observations , between 1837 and 1840 , of 61 Cygni , a star ...
... parallax 1 " .16 . His successor at the Cape , Maclear , reduced this to o " .92 . In 1835 Struve assigned a doubtful parallax of o " .261 to Vega ( a Lyræ ) . But Bessel's observations , between 1837 and 1840 , of 61 Cygni , a star ...
Page 163
... parallax amounting to a twentieth of a second of arc . Among these are Canopus , a Orionis , a Cygni , ẞ Centauri , and 7 Cassiopeia . Oude- mans has published a list of parallaxes observed . Proper Motion . In 1718 Halley detected 1 ...
... parallax amounting to a twentieth of a second of arc . Among these are Canopus , a Orionis , a Cygni , ẞ Centauri , and 7 Cassiopeia . Oude- mans has published a list of parallaxes observed . Proper Motion . In 1718 Halley detected 1 ...
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accurate Airy ancient astron Astronomer Royal astronomical units bright calculations Cape catalogue centre century Chaldæans Chinese comet Copernicus diameter discovered discovery earth Egyptian epicycles equatorial error excentric explain fact fixed stars Galileo Greenwich Halley heavenly bodies heavens heliometer Hipparchus History of Astronomy instruments JOHANNES KEPLER John Herschel Jupiter Jupiter's Kepler Laplace Lick Observatory light line of apses line of sight lunar Mars mathematical mean distance mean motion measured ment Mercury meteor miles a second moon moon's nebulæ Newton observations Observatory orbit parallax period photographic physical planet planetary pole position predicted proper motion proved Ptolemy R. S. Phil records refractor retrograde retrograde motion revolving round ring rotation satellites Saturn seems showing Sir William Herschel Sirius solar eclipse solar system spectra spectroscope spectrum sphere spots stellar sun-spot supposed tables telescope theory tion Trans Tycho Brahe universal gravitation Uranus velocity Venus Verrier
Popular passages
Page 67 - that every particle of matter in the universe attracts every other particle, with a force whose direction is that of the line joining the two, and whose magnitude is directly as the product of their masses, and inversely as the square of their distances from each other.
Page 26 - So he sate and cunningly guided the craft with the helm, nor did sleep fall upon his eyelids, as he viewed the Pleiads and Bootes, that setteth late, and the Bear, which they likewise call the Wain, which turneth ever in one place, and keepeth watch upon Orion, and alone hath no part, in the baths of Ocean. This star, Calypso, the fair goddess, bade him to keep ever on the left as he traversed the deep.
Page 53 - The third, viz. that the squares of the periodic times are proportional to the cubes of the mean distances...
Page 79 - Wherefore if according to what we have already said it should return again about the year 1758, candid posterity will not refuse to acknowledge that this was first discovered by an Englishman.
Page 122 - ... They have not been regarded as so successful as his geometrical analysis of the observed phenomena. It is only just to add that he himself did not attach equal weight to them ; for in answer to objections urged by Lalande to his theory that the spots are depressions, Wilson wrote thus in 1783 : — ' Whether their first production and subsequent numberless changes depend upon the eructation of elastic vapours from below, or upon eddies or whirlpools commencing at the surface, or upon the dissolving...
Page 51 - He then said boldly that it was impossible that so good an observer as Tycho could be wrong by eight minutes* and added, " out of these eight minutes we will construct a new theory that will explain the motions of all the planets.