A Popular Grammar of the Elements of Astronomy: Adapted to the Use of Students and Public SchoolsSherwood and Company, 1836 - 287 pages |
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Common terms and phrases
altitude angle aphelion apparent diameter appear apsides Aries ascending node astronomical atmosphere axis Boötes called celestial centre Ceres circle comet conjunction constellation degrees digits eclipsed direction disc diurnal motion double stars earth earth's orbit earth's shadow equal equinoctial equinox fixed stars geocentric longitude globe greatest equation heavenly body heavens heliocentric hemisphere Hence Herschel horary motion horizon horizontal parallax Illus inclination inferior conjunction inferior planet Jupiter latitude less Libra light limb longitude lunar magnitude Mars mean distance Mercury milky millions of miles minutes moon's orbit move nearest nearly nebulæ nebulosity nebulous matter northern obliquity observed opposition orbit Pallas parallax perihelion perpendicular Plate quadratures radius refraction retrograde revolves round right ascension ring rotation round the sun satellites Saturn seconds seen semidiameter solar system spots sun and moon sun's superior planet supposed surface syzygies telescope tion umbra Uranus velocity Venus Vesta visible
Popular passages
Page 115 - I have often seen double and treble nebulae variously arranged ; large ones with small seeming attendants ; narrow, but much extended lucid nebulae or bright dashes ; some of the shape of a fan, resembling an electric brush issuing from a lucid point; others of the cometic shape, with a seeming nucleus in the centre, or like cloudy stars, surrounded with a nebulous atmosphere...
Page 36 - ... show that heat is produced by the sun's rays only when they act on a calorific medium: they are the cause of the production of heat, by uniting with the matter of fire which is contained in the substances that are heated...
Page 120 - ... in diameter. The star is perfectly in the centre, and the atmosphere is so diluted, faint, and equal throughout, that there can be no surmise of its consisting of stars ; nor can there be a doubt of the evident connection between the atmosphere and the star. Another star not much less in brightness, and in the same field with the above, was perfectly free from any such appearance.
Page 130 - From this it follows, that not only our sun, but all the stars we can see with the eye, are deeply immersed in the milky way, and form a component part of it.
Page 31 - Day, is the time in which any star appears to revolve from the meridian to the meridian again ; or the time in which the earth makes one complete revolution on its axis, which is 23 hours 56...
Page 121 - The end I have had in view, by arranging my observations in the order in which they have been placed, has been to shew, that the above mentioned extremes may be connected by such nearly allied intermediate steps, as will make it highly probable that every succeeding state of the nebulous matter...
Page 61 - ... the slower she moves. When the earth is in its perihelion, or nearest the sun, the periodical time of the moon is the greatest. The earth is at its perihelion in winter, and...
Page 98 - For if our own solar system be conceived to change its place with respect to absolute space, this might, in process of time, occasion an apparent change in the angular distances of the fixed stars; and in such a case, the places of the nearest stars being more affected than of those that are very remote, their relative positions might seem to alter, though the stars themselves were really immovable. And on the other hand, if our own system be at rest and any of the stars really in motion, this might...
Page 115 - are arranged into strata, and run on to a great length, and some of them I have been able to pursue, and to guess pretty well at their form and direction. It is probable enough that they may surround the whole starry sphere of the heavens, not unlike the...