Zitate von Wilhelm Herschel
Wilhelm Herschel
Geburtstag: 15. November 1738
Todesdatum: 25. August 1822
Friedrich Wilhelm Herschel war ein aus Deutschland stammender britischer Astronom und Musiker.
Zitate Wilhelm Herschel
„This tends to confirm the hypothesis that all are composed of stars more or less remote.“
Ch.4 "Life and Works"
Kontext: Nebulæ can be selected so that an insensible gradation shall take place from a coarse cluster like the Pleiades down to a milky nebulosity like that in Orion, every intermediate step being represented. This tends to confirm the hypothesis that all are composed of stars more or less remote.
„I have availed myself of the labors of preceding astronomers, but have been induced thereto by my own actual observation of the solar phenomena.“
Ch.4 "Life and Works" quote from his paper "Nature and Construction of the Sun and Fixed Stars" (1795).
Kontext: I should not wonder if, considering all this, we were induced to think that nothing remained to be added; and yet we are still very ignorant in regard to the internal construction of the sun.... The spots have been supposed to be solid bodies, the smoke of volcanoes, the scum floating on an ocean of fluid matter, clouds, opaque masses, and to be many other things.... The sun itself has been called a globe of fire, though, perhaps, metaphorically.... It is time now to profit by the observations we are in possession of. I have availed myself of the labors of preceding astronomers, but have been induced thereto by my own actual observation of the solar phenomena.<!-- p. 145-146
„The starlike appearance of the following six nebulæ is so considerable that the best description… was to compare them to stars with certain deficiencies.“
Astronomical Observations relating to the Construction of the Heavens... (1811)
Kontext: The starlike appearance of the following six nebulæ is so considerable that the best description... was to compare them to stars with certain deficiencies.<!-- p. 328
„Nebulæ can be selected so that an insensible gradation shall take place“
Ch.4 "Life and Works"
Kontext: Nebulæ can be selected so that an insensible gradation shall take place from a coarse cluster like the Pleiades down to a milky nebulosity like that in Orion, every intermediate step being represented. This tends to confirm the hypothesis that all are composed of stars more or less remote.
„We may conceive that, perhaps in progress of time these nebulæ which are already in such a state of compression, may be still farther condensed so as actually to become stars.“
Astronomical Observations relating to the Construction of the Heavens... (1811)
Kontext: We may conceive that, perhaps in progress of time these nebulæ which are already in such a state of compression, may be still farther condensed so as actually to become stars.<!-- p. 318
„It will be necessary to explain the spirit of the method of arranging the observed astronomical objects under consideration in such a manner, that one shall assist us to understand the nature and construction of the other.“
Astronomical Observations relating to the Construction of the Heavens... (1811)
Kontext: It will be necessary to explain the spirit of the method of arranging the observed astronomical objects under consideration in such a manner, that one shall assist us to understand the nature and construction of the other. This end I propose to obtain by assorting them into as many classes as will be required to produce the most gradual affinity... and it will be found that those contained in one article, are so closely allied to those in the next, that there is perhaps not so much difference between them... as there would be in an annual description of the human figure were it given from the birth of a child till he comes to be a man in his prime.<!-- p. 270-271
„That the emission of light must waste the sun, is not a difficulty that can be opposed to our hypothesis.“
Ch.4 "Life and Works" quote from his paper "Nature and Construction of the Sun and Fixed Stars" (1795).
Kontext: That the emission of light must waste the sun, is not a difficulty that can be opposed to our hypothesis. Many of the operations of Nature are carried on in her great laboratory which we cannot comprehend. Perhaps the many telescopic comets may restore to the sun what is lost by the emission of light.<!-- p. 148
„In future… we shall look upon those regions into which we may now penetrate by means of such large telescopes, as a naturalist regards a rich extent of ground or chain of mountains containing strata variously inclined and directed, as well as consisting of very different materials. The surface of a globe or map therefore will but ill delineate the interior parts of the heavens.“
Ch.4 "Life and Works" from a memoir (1784).
„It is very probable that the great stratum called the Milky Way is that in which the sun is placed, though perhaps not in the very centre of its thickness.“
Ch.4 "Life and Works".
Kontext: It is very probable that the great stratum called the Milky Way is that in which the sun is placed, though perhaps not in the very centre of its thickness.... We gather this from the appearance of the Galaxy, which seems to encompass the whole heavens, as it certainly must do if the sun is within it.<!-- p. 159-160
„An object may not only contain stars, but also nebulosity not composed of them.“
Astronomical Observations relating to the Construction of the Heavens... (1811)
Kontext: An object may not only contain stars, but also nebulosity not composed of them.<!-- p. 270
„A knowledge of the construction of the heavens has always been the ultimate object of my observations…“
Astronomical Observations relating to the Construction of the Heavens... (1811)
„It is evident that we cannot mean to affirm that the stars of the fifth, sixth, and seventh magnitudes are really smaller than those of the first, second, or third, and that we must ascribe the cause of the difference in the apparent magnitudes of the stars to a difference in their relative distances from us.“
Ch.4 "Life and Works" from a memoir, published (1817).
Kontext: It is evident that we cannot mean to affirm that the stars of the fifth, sixth, and seventh magnitudes are really smaller than those of the first, second, or third, and that we must ascribe the cause of the difference in the apparent magnitudes of the stars to a difference in their relative distances from us. On account of the great number of stars in each class, we must also allow that the stars of each succeeding magnitude, beginning with the first, are, one with another, further from us than those of the magnitude immediately preceding.
„This consideration must alter the form of our proposed inquiry; for the question being thus at least partly decided, since it is ascertained that we have rays of heat which give no light, it can only become a subject of inquiry whether some of these heat-making rays may not have a power of rendering objects visible, superadded to their now already established power of heating bodies.“
This being the case, it is evident that the onus probandi [burden of proof] ought to lie with those who are willing to establish such an hypothesis, for it does not appear that Nature is in the habit of using one and the same mechanism with any two of our senses. Witness the vibration of air that makes sound, the effluvia that occasion smells, the particles that produce taste, the resistance or repulsive powers that affect the touch—all these are evidently suited to their respective organs of sense.
Ch.4 "Life and Works" on his discovery of the infrared.
„A standard of reference for the arrangement of the stars may be had by comparing their distribution to a certain properly modified equality of scattering. The equality which I propose does not require that the stars should be at equal distances from each other, nor is it necessary that all those of the same nominal magnitude should be equally distant from us.“
Ch.4 "Life and Works" from a memoir, published (1817).
„The number of compound nebulæ… being so considerable, it will follow, that if they owe their origin to the breaking up of some former extensive nebulosities of the same nature with those which have been shewn to exist at present, we might expect that the number of separate nebulæ should far exceed the former, and that moreover these scattered nebulas should be found not only in great abundance, but also in proximity or continuity with each other… Now this is exactly what by observation, we find to be the state of the heavens.“
p, 125
Astronomical Observations relating to the Construction of the Heavens... (1811)
„When I resided at Bath I had long been acquainted with the theory of optics and mechanics, and wanted only that experience so necessary in the practical part of these sciences. This I acquired by degrees at that place where in my leisure hours, by way of amusement, I made several two-foot, five-foot, seven-foot, ten-foot and twenty-foot Newtonian telescopes, beside others, of the Gregorian form, of eight, twelve, and eighteen inches, and two, three, five, and ten feet focal length. In this way I made not less than two hundred seven-foot, one hundred and fifty ten-foot, and about eighty twenty-foot mirrors, not to mention the Gregorian telescopes.“
Ch.4 "Life and Works" Footnote: At least one of these telescopes had the principal mirror made of glass instead of metal. Philosophical Transactions of the Royal Society of London (1803).