Astronomical Register: A Medium of Communication for Amateur Observers and All Others Interested in the Science of Astronomy, Volume 17J. D. Potter., 1880 |
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Common terms and phrases
1st Oc 1st Sh 1st Tr 2nd Oc 2nd Sh 2nd Tr 3rd Oc 3rd Sh Admiral Smyth Algol angle appeared Astronomer-Royal Astronomical Register Baxendell bright lines catalogue Christie chromosphere clouds colour comet Conjunction of Moon corona Deimos diameter disk distance double stars Draper drawings eclipse Encel sp equatorial error Greenwich Harvard College Observatory heliometer Herschel hour Hyginus inferior conjunction John Herschel Jupiter Jupiter's Satellites Klein light limb Lord Lindsay lunar Mädler magnitude Mare Crisium Mars Mean Noon Mercury meteoric Mimas nf Mimas sp moon's Neison night object observations Observatory Occultation orbits paper Peirce Phobos photographs Picard planet polarization portion of disc Proclus Prof proper motion Ranyard Reappearance of ditto refractor region Rhea Sadler Saturn seen shadow Sidereal solar spectrum streak Sun's Meridian Passage surface Tauri telescope Terminator Tethys nf Thur tion Tues Uranus Venus visible Winnecke
Popular passages
Page 44 - ... posterity : but the record remains, and transfuses all its own exactness into every determination which takes it for a groundwork, giving to inferior instruments, nay even to temporary contrivances, and to the observations of a few weeks or days, all the precision attained originally at the cost of so much time, labour, and expense.
Page 113 - We know in other ways that meteoric matter is constantly falling upon the earth. Yet there is a strange interest in the actual recognition of this cosmical dust. What Humboldt said of the larger meteoric masses which have fallen visibly upon the earth from interplanetary space is true (with slight change) of these more subtle signs of the earth's passage through cosmical dust : — ' Accustomed to know non-telluric bodies solely by measurement, by calculation, and by the inferences of our reason,...
Page 213 - He acts upon the principle that if a thing is worth doing at all it is worth doing well : — and the thing that he " does" especially well is the public.
Page 211 - ... to be maintained. An increase of five thousand dollars a year for five years has been solicited, and if obtained will, during that time, more than double the scientific results of the Observatory, whose endowment, grounds, buildings, instruments, and library, represent a sum of more than $300,000. But little remains to be promised in order to secure the whole. If this can be done, rapid progress can be made in the publication of the accumulated mass of past observations, which are in danger of...
Page 154 - Leyden jars, communicate an intense incandescence to air, and light enough is produced to permit of the use of a narrow slit, and of a collimator and telescope of long focus. Since 1877, when the first publication of the discovery of oxygen in the Sun was made, still further improvements, especially in the optical parts, have been completed, so that I am now enabled to photograph the oxygen spectrum with four times the dispersion then employed. For the sake of clearness, it is best to give a brief...
Page 156 - ... revolutions of the bobbin of the Gramme machine. In the last three years the Gramme has made 20 millions of revolutions. The petroleum engine only consumes a couple of drops of oil at each stroke, and yet it has used up about 150 gallons. Each drop of oil produces two or three 10inch sparks.
Page 66 - ... but to an important amount when large areas of the moon's surface are considered. Remembering the effects which take place on our earth, in the mere change from the frost of winter to the moderate warmth of early spring, it is difficult to conceive that such remarkable contraction and expansion can take place in a surface presumably less coherent than the relatively moist and plastic substances comprising the terrestrial crust, without gradually effecting the demolition of the steeper lunar elevations....
Page 187 - The general conclusion that follows from these results, is, that on this occasion we have ascertained the true nature of the corona, viz : it shines by light reflected from the sun by a cloud of meteors surrounding that luminary, and that on former occasions it has been infiltrated with materials thrown up from the chromosphere, notably with the 1474 matter and hydrogen. As the chromosphere is now quiescent this infiltration has taken place to a scarcely perceptible degree recently. This explanation...
Page 167 - It would appear on different sides of the planet in the same night, and at first I thought there were two or three inner moons, since it seemed to me at that time very improbable that a satellite should revolve around its primary in less time than that in which the primary rotates. To decide this point I watched this moon throughout the nights of August 20 and 21, and saw that there was in fact but one inner moon, which made its revolution around the primary in less than one-third the time of the...
Page 159 - There seems to be still a great question as to whether the solar spectrum is made up only of bright and dark lines, or whether there is a background of continuous spectrum. I am not disposed to give up the idea that we have a continuous spectrum underlying these dark lines, but think that it is certain that we have also bright lines mixed with the dark. We know that when we look at...