United States or Central African Republic ? Vote for the TOP Country of the Week !
With the aid of the map we find the position of the new star of 1866, which is famous as the first so-called temporary star to which spectroscopic analysis was applied. When first noticed, on May 12, 1866, this star was of the second magnitude, fully equaling in brilliancy alpha, the brightest star of the constellation; but in about two weeks it fell to the ninth magnitude.
I must leave it to others to describe the progress of that splendid series of spectroscopic discoveries by which the chemistry of the heavenly bodies has been brought within the range of human inquiry.
Telescopes and the spectroscopic camera were trained in the right direction, magnetic instruments were set to run at quick speed, and observers were told off to watch everything on which the absence of sun could possibly have the smallest effect. Everything, in short, was ready except the sun itself which obstinately refused to come out.
Spectroscopic indications, again, give hope of eventually affording a fixed point of comparison with terrestrial heat sources; but their interpretation is still beset with uncertainties; nor can, indeed, the expression of transcendental temperatures in degrees of impossible thermometers be, at the best, other than a futile attempt to convey notions respecting a state of things altogether outside the range of our experience.
Certain spectroscopic coincidences, avowedly only approximate, suggesting that stars and nebulæ of every species might be formed out of variously aggregated meteorites, failed of verification by exact inquiry. And spectroscopic coincidences admit of no compromise. Those that are merely approximate are, as a rule, unmeaning.
Thus in the Great Bear, beta, gamma, delta, epsilon, zeta, all agree as to angular proper motion. delta was too faint for a spectroscopic measurement, but all the others have been shown to be approaching us at a rate of twelve to twenty miles a second. The same has been proved for proper motion, and line of sight motion, in the case of Pleiades and other groups.
Spectroscopic and photographic apparatus are simply additions to the telescope. They do not supersede or render it of less importance. On the contrary, the efficacy of their action depends primarily upon the optical qualities of the instruments they are attached to.
Spectroscopic indications of aqueous vapour as present in the atmosphere of Venus, were obtained in 1874 and 1882, by Tacchini and Riccò in Italy, and by Young in New Jersey.
We have no reason to suspect the sun of any latent eccentricities, like those that have been displayed by "temporary" stars; yet, acting on the principle which led the old emperor-astrologer Rudolph II to torment his mind with self-made horoscopes of evil import, let us unscientifically imagine that the sun could suddenly burst out with several hundred times its ordinary amount of heat and light, thereby putting us into a proper condition for spectroscopic examination by curious astronomers in distant worlds.
Lastly, in that glorious appendage, the solar corona, which extends for hundreds of thousands of miles from the sun's surface, there are enormous quantities of some element, whose nature is as yet unknown, showing under spectroscopic analysis the bright line which seems to have appeared in the spectrum of the flaming sun in the Swan.
Word Of The Day