Astronomy simplified1838 - 120 pages |
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actual affluxes amidst aphelion appears astronomical atmosphere attained augment axis behold binary stars celestial bodies celestial ecliptic centre Ceres circumference clusters Comet comprising condensation consequently constellation course round crossing point degrees diameter disc distance diverging double ring double star earthly equator equatorial equatorial line exhibit Flamstead globe heat Hence horizon illuminated immense inclination infinitude inhabitants irradiated Jupiter Jupiter's luminaries lunar magnificence magnitude Mars's Mercury mighty miles an hour Milky millions of miles minutes moon moon's motion nearly Nebula nebulosity observations opposite orbits oscillatory rotation particles perihelion point period planetary system polar star poles portion position present northern primary planets propelling relative remarkable remote revolution revolves round rotatory round the Earth round the Sun Saturn side Sir John Herschel Sir William Herschel solar rays solar system southern hemisphere space specific spectator spiral courses splendour stupendous Sun's surface surrounding telescopes thousand miles tion velocity Venus Vesta vicinity visible zone
Popular passages
Page 109 - This remarkable law of variation appears strongly to suggest the revolution round it of some opaque body, which, when interposed between us and Algol, cuts off a large portion of its light. " It is,
Page 106 - In such instances, the larger star is usually of a ruddy or orange hue, while the smaller one appears blue or green, probably in virtue of that general law of optics, which provides that, when the retina is under the influence of excitement by any...
Page 125 - Another, in the constellation Andromeda, presents a visible disk of 12", perfectly defined and round. Granting these objects to be equally distant from us with the stars, their real dimensions must be such as would fill, on the lowest computation, the whole orbit of Uranus. It is no less evident that, if they be solid bodies of a solar nature, the intrinsic splendor of their surfaces must be almost infinitely inferior to that of the sun's.
Page 125 - They have, as their name imports, exactly the appearance of planets ; round or slightly oval disks, in some instances quite sharply terminated, in others a little hazy at the borders, and of a light exactly equable or only a very little mottled, which, in some of them, approaches in vividness to that of actual planets.
Page 121 - ... ten or twenty thousand stars, compacted and wedged together in a round space, whose angular diameter does not exceed eight or ten minutes ; that is to say, in an area not more than a tenth part of that covered by the moon.
Page 109 - Uranus about the sun ; and the correspondence between their calculated and observed places, in such elongated ellipses, must be admitted to carry with it a proof of the prevalence of the Newtonian law of gravity in their systems, of the very same nature and cogency as that of the calculated and observed places of comets round the centre of our own system.
Page 63 - Many doubted, many positively refused to believe, so novel an announcement ; all were struck with the greatest astonishment, according to their respective opinions, either at the new view of the universe thus offered to them, or at the high audacity of Galileo, in inventing such fables.
Page 123 - ... seen projected, and (owing to its greater distance) appearing like it to consist of stars much smaller than those in other parts of the heavens. "Can it be,'' asks Sir J. Herschel, " that we have here a brother system, bearing a real physical resemblance and strong analogy of structure to our own ?
Page 123 - ... than the rest; the stars of the Milky Way are scattered over it in the same manner as over the ,rest of the heavens. Its extent in the parallel is nearly one degree and half, and in the meridional direction about fifty-two minutes.
Page 120 - And as this latter immense starry bed is not of equal breadth or lustre in every part, nor runs on in one straight direction, but is curved and even divided into two streams along a very considerable portion of it, we may likewise expect the greatest variety in the strata of the clusters of stars and nebula.