The summer is almost nightless, print being legible at midnight, but in winter the days are only six hours long, though the nights are frequently illuminated with brilliant displays of the aurora borealis.
3 Mirage and similar phenomena and the aurora are common.
Original romance writing, which may be said to have commenced with Dugonics and Kaman at the close of the 18th, and to have found a representative in Francis Verseghy at the beginning of the 19th century, was afterwards revived by Fay in his Belteky hdz (1832), and by the contributors to certain literary magazines, especially the Aurora, an almanack conducted by Charles Kisfaludy, 1821-1830, and continued by Joseph Bajza to 1837.
Of later magazines the Australian (1878-1881), Aurora australis (1868), and the Sydney Magazine (1878), were the most noteworthy.
With him in France were his grandsons, William Temple Franklin, William Franklin's natural son, who acted as private secretary to his grandfather, and Benjamin Franklin Bache (1769-1798), Sarah's son, whom he sent to Geneva to be educated, for whom he later asked public office of Washington, and who became editor of the Aurora, one of the leading journals in the Republican attacks on Washington.
In 1823 he was admitted to the bar, and began practice at Aurora, New York, to which place his father had removed.
He was the first, in 1867, to examine the spectrum of the aurora borealis, and detected and measured the characteristic bright line in its yellow green region; but he was mistaken in supposing that this same line, which is often called by his name, is also to be seen in the zodiacal light.
From 1821 to 1826 he published many separate poems of great beauty in the Aurora, Hebe, Aspasia, and other magazines of polite literature.
AURORA, a city of Kane county, Illinois, U.S.A., in the N.E.
Aurora is served by the Chicago, Burlington & Quincy, the Chicago & North-Western, the EIgin, Joliet & Eastern, and the Illinois, Iowa and Minnesota railways, and is connected with Chicago by an electric line.
Aurora is an important manufacturing centre; among its manufactures are railway cars - the shops of the Chicago, Burlington & Quincy railway being 927 here - flour and cotton, carriages, hardware specialties, corsets, suspenders, stoves and silver-plate.
The first settlement in the vicinity of Aurora was made in 1834.
In 1845 the village of East Aurora was incorporated, and West Aurora was incorporated nine years later.
Aurora, Missouri >>
'ABAYE, the name of a Babylonian aurora, born in the middle of the 3rd century.
AURORA POLARIS (Aurora Borealis and Australis, Polar Light, Northern Lights), a natural phenomenon which occurs in many forms, some of great beauty.
This accounts for the description of aurora as " Merry Dancers."
A fully developed corona is perhaps the finest form of aurora.
(7) Diffused Aurora.
Isochasms. - Aurora is seldom observed in low latitudes.
Fritz (2) has, however, drawn a series of curves which are believed to give a good general idea of the relative frequency of aurora throughout the northern hemisphere.
Fritz' curves, shown in the illustration, are termed isochasms, from the Greek word employed by Aristotle to denote aurora.
Starting from the equator and travelling northwards we find in the extreme south of Spain an average of only one aurora in ten years.
shows the annual variation observed in the frequency of aurora.
between higher and middle latitudes, a primary consideration is that aurora is seldom seen until the sun is some degrees below the horizon.
There is no reason to suppose that the physical causes whose effects we see as aurora are in existence only when aurora is visible.
Until means are devised for detecting aurora during bright sunshine, our knowledge as to the hour at which these causes are most frequently or most powerfully in operation must remain incomplete.
In high latitudes for several months in summer it is never dark, and consequently a total absence of visible aurora is practically inevitable.
Whether there is any real difference between high and mean latitudes in the annual frequency of the causes rendered visible by aurora, it is difficult to say.
loo 82 57 46 8 Out of a total of 1714 hours during which the sky was wholly overcast the Swedish expedition saw auroras on 17, occurring on 14 separate days, whereas 226 hours of aurora would have occurred out of an equal number of hours with the sky quite clear.
It is only during winter and in high latitudes that we can hope to ascertain anything directly as to the real diurnal variation of the causes whose influence is visible at night as aurora.
gives particulars of the number of occasions when aurora was seen at each hour of the twenty-four during three expeditions in high latitudes when a special outlook was kept.
- The action of moonlight necessarily gives rise to a true lunar period in the visibility of aurora.
The extent to which it renders aurora invisible depends, however, so much on the natural brightness of the aurora - which depends on the time and the place - and on the sharpness of the outlook kept, that it is difficult to gauge it.
The connexion between aurora and earth magnetic disturbances renders it practically certain that if a 26-day or similar period exists in the one phenomenon it exists also in the other, and of the two terrestrial magnetism is probably the element least affected by external complications, such as the action of moonlight.
Thus there must in general be a difference between the observer's magnetic meridian - answering to the mean position of the magnetic needle at his station - and the direction the needle would have at a given hour, if undisturbed by the aurora, at any spot where the phenomena which the observer sees as aurora exist.
Relations to Magnetic Storms. - That there is an intimate connexion between aurora when visible in temperate latitudes and terrestrial magnetism is hardly open to doubt.
A bright aurora visible over a large part of Europe seems always accompanied by a magnetic storm and earth currents, and the largest magnetic storms and the most conspicuous auroral displays have occurred simultaneously.
On some of these occasions aurora was brilliant in both the northern and southern hemispheres, whilst magnetic disturbances were experienced the whole world over.
Arctic observers, both Danish and British, have repeatedly reported displays of aurora unaccompanied by any special magnetic disturbance.
When there has been much apparent movement, and brilliant changes of colour in the aurora, magnetic disturbance has nearly always accompanied it.
In the northern hemisphere to the south of the zone of greatest frequency, the part of the sky in which aurora most generally appears is the magnetic north.
The relative frequency in the two positions seems to vary with the hour, the type of aurora, probably with the season of the year, and possibly with the position of the year in the sun-spot cycle.
The calculated heights - all referring to the lowest border of the aurora - varied from o 6 to 67.8 km.
General Sabine, Sir John Franklin, Prof. Selim Lemstrom, Dr David Walker (at Fort Kennedy in 1858-1859), Captain Parry (Fort Bowen, 1825) and others - have seen aurora below the clouds or between themselves and mountains.
The ordinary colour of aurora is white, usually with a distinct yellow tint in the brighter forms, but silvery white when the light is faint.
The spectrum of aurora consists of a number of lines.
This line is so characteristic that its presence or absence is the usual criterion for deciding whether an atmospheric light is aurora.
The Swedish Expedition (17) of 1899-1902, engaged in measuring an arc of the meridian in Spitsbergen, were unusually well provided spectrographically, and succeeded in taking photographs of aurora in conjunction with artificial lines-chiefly of hydrogen-which led to results claiming exceptional accuracy.
If, as is now generally believed, aurora represents some form of electrical discharge, it is only reasonable to suppose that the auroral lines arise from atmospheric gases.
The conditions, however, as regards pressure and temperature under which the hypothetical discharges take place must vary greatly in different auroras, or even sometimes in different parts of the same aurora.
Many of the auroral lines seen in any single aurora are exceedingly faint, so that even their relative positions are difficult to settle with high precision.
If sound waves originate at the seat of auroral displays they seem hardly likely to be audible on the earth, unless the aurora comes very low and great stillness prevails.
there can be no doubt that distinct sound does occasionally accompany certain displays of aurora."
On the one occasion when Captain Dawson says he heard it himself, " the sound was like the swishing of a whip or the noise produced by a sharp squall of wind in the upper rigging of a ship, and as the aurora brightened and faded so did the sound which accompanied it."
If under these conditions the sound was really due to the aurora, the latter, as Captain Dawson himself remarks, must have been pretty close.
Several Arctic observers,however,especially Paulsen (18) have observed a diminution of positive potential, or even a change to negative, for which they could suggest no explanation except the presence of a bright aurora.
Artificial Phenomena resembling Aurora.-At Sodankyla, the station occupied by the Finnish Arctic Expedition of 1882-1883, Selim Lemstrom and Biese (23) described and gave drawings of optical phenomena which they believed to be artificially produced aurora.
Sometimes a Holtz machine was employed, but even without it illumination resembling aurora was seen on several occasions, extending apparently to a considerable height.
Birkeland (19) has produced phenomena bearing a striking resemblance to several forms of aurora.
Theories.-A great variety of theories have been advanced to account for aurora.
The ionized condition must be supposed to last to a greater or less extent for a good many hours to account for aurora being seen throughout the whole night.
Fritz, Das Polarlicht (Leipzig, 1881); (3) Svante August Arrhenius, Lehrbuch der kosmischen Physik; (4) Joseph Lovering, " On the Periodicity of the Aurora Borealis," Mem.
In 1766 he received a gold medal from the Academy of Sciences for an essay on the best means of lighting a large town; and among his early work were papers on the analysis of gypsum, on thunder, on the aurora and on congelation, and a refutation of the prevalent belief that water by repeated distillation is converted into earth.
Halley's most notable scientific achievements were - his detection of the "long inequality" of Jupiter and Saturn, and of the acceleration of the moon's mean motion (1693), his discovery of the proper motions of the fixed stars (1718), his theory of variation (1683), including the hypothesis of four magnetic poles, revived by C. Hansteen in 1819, and his suggestion of the magnetic origin of the aurora borealis; his calculation of the orbit of the 1682 comet (the first ever attempted), coupled with a prediction of its return, strikingly verified in 1759; and his indication (first in 1679, and again in 1716, Phil.
The expedition left Hobart in the " Aurora " on Dec. 2 1911, and after landing a party with a wireless installation on Macquarie I.
The " Aurora " proceeded westward close along the Antarctic circle.
The " Aurora " returned to Hobart.
8 when he reached the hut and saw the " Aurora," but she was outward bound.
The " Aurora " returned to Commonwealth Bay on Dec. 13 1913, and after taking the base party on board made another voyage to Queen Mary Land and carried out valuable oceanographical work on the way back to Hobart.
On the Ross Sea side the " Aurora," under command of Capt.
The " Aurora " reached Cape Evans on Jan.
On May 6 1915 the " Aurora," which had been frozen in and made fast by many cables to the shore at Cape Evans, was blown out to sea with all the ice and was held fast for 315 days, during which time she drifted northward through Ross Sea nearly in the same direction and at nearly the same rate as the " Endurance " was drifting at the same time in the Weddell Sea.
All of the 53 men who returned from the expeditions of the " Endurance " and " Aurora " served in the navy, army or air force during the World War, three being killed and five wounded.
Davis, With the "Aurora" in the Antarctic (1920); Sir E.
electricity is discussed in Electromagnetism, and these manifestations in nature in Atmospheric Electricity; Aurora Polaris and Terrestrial magnetism.
Hammarskold's society was succeeded in 1807 by the famous " Aurora m.
The German king, Henry the Fowler, his wife Matilda, and Aurora, countess of KiMigsmark, the mistress of Augustus the Strong, are buried in the Schlosskirche.
Arago is also fairly entitled to be regarded as having proved the long-suspected connexion between the aurora borealis and the variations of the magnetic elements.
His researches on the last-mentioned subject led him to form a new theory of the aurora borealis.
An investigation of the great aurora of the 4th of February 1872 led him to refer such phenomena to a distinct branch of science, designated by him "cosmical meteorology"; but he was not destined to prosecute the subject.
Elgin is served by the Chicago & NorthWestern and the Chicago, Milwaukee & St Paul railways, and by interurban electric railways to Chicago, Aurora and Belvidere.
1 (Aurora g n?
Among these subjects were the transit of Mercury, the Aurora Borealis, the figure of the earth, the observation of the fixed stars, the inequalities in terrestrial gravitation, the application of mathematics to the theory of the telescope, the limits of certainty in astronomical observations, the solid of greatest attraction, the cycloid, the logistic curve, the theory of comets, the tides, the law of continuity, the double refraction micrometer, various problems of spherical trigonometry, &c. In 1742 he was consulted, with other men of science, by the pope, Benedict XIV., as to the best means of securing the stability of the dome of St Peter's, Rome, in which a crack had been discovered.
Tromholt, Under the Rays of the Aurora Borealis (London, 1885); Y.
Dallas was United States attorney for the eastern district of Pennsylvania from 1801 until 1814, a period marked by bitter struggles between the DemocraticRepublican factions in the state, in which he took a leading part in alliance with Governor Thomas M ` Kean and Albert Gallatin, and in opposition to the radical factions led by Michael Leib (1759-1822) and William Duane (1760-1835), of the Aurora.
Evidence is also accumulating to show that the sun and stars are radio-active bodies, and that emanations proceeding from the sun, and reaching the earth, have important relations to the phenomena of Terrestrial Magnetism and the Aurora.
The conclusions which researches relating to it have so far reached are treated in the articles STAR; SUN; COMET; NEBULA; AURORA POLARIS, &C. (S.
At Nuremberg he published in 1733 a collection of 316 observations of the aurora borealis made by himself and others 1716-1732.
AURORA, a city of Lawrence county, Missouri, U.S.A., 275 m.
Farming and fruit-growing are carried on in the surrounding country, and Aurora is the place from which the products are shipped.
Aurora was platted in 1870 and was chartered as a city in 1886.
Aurora, New York >>
5567), and concluded that in the zodiacal light there was the same material as is found in the aurora and in the solar corona, and probably through all space.
Upsala, however, is a place where the auroral spectrum can often be observed in the sky, even when no aurora is visible, and it has generally been believed that what Angstrom really saw was an auroral and not a zodiacal spectrum.
He's the cabin boy on board the luxury airship, the Aurora.
I do not recall ever seeing the Aurora more active.
Until one observes an Aurora of this intensity, it is difficult to appreciate the scale and speed of the constant changes in patterns.
The word usage examples above have been gathered from various sources to reflect current and historial usage. They do not represent the opinions of YourDictionary.com.