The line of the equinoxes is the imaginary diameter of the celestial sphere which joins them.
It was considered by Biot to have been originally twenty-four, but to have been enlarged to twenty-eight about i ioo B.C., by the addition of determinants for the solstices and equinoxes of that period.
in Europe the frequency near the equinoxes rises above that at midwinter, and we have a distinct double period, with a principal minimum at midsummer and a secondary minimum at midwinter.
Each day of the week was marked by the adoration of a special planet, the sun being the most sacred of all, and certain dates, perhaps the sixteenth of each month and the equinoxes, in conformity with the character of Mithras as mediator, were set aside for special festivals.
The 12-hour term is much less variable, especially as regards its phase angle; its amplitude shows distinct maxima near the equinoxes.
Owing to the precession of the equinoxes it is longer than a tropical or sidereal year by 25 minutes and 2.3 seconds.
trepidare, to tremble), a term meaning, in general, fear or trembling, but used technically in astronomy for an imagined slow oscillation of the ecliptic, having a period of 7000 years, introduced by the Arabian astronomers to explain a supposed variation in the precession of the equinoxes.
Violent winds are common at both equinoxes.
The hours of the day and night were of course only equal at the time of the equinoxes.
In The Arrangement Of The Civil Year, Two Objects Are Sought To Be Accomplished, First, The Equable Distribution Of The Days Among Twelve Months; And Secondly, The Preservation Of The Beginning Of The Year At The Same Distance From The Solstices Or Equinoxes.
About The Year 73 O The Venerable Bede Had Already Perceived The Anticipation Of The Equinoxes, And Remarked That These Phenomena Then Took Place About Three Days Earlier Than At The Time Of The Council Of Nicaea.
KOXos, shortened, and ovpfi, tail), in astronomy, either of the two principal meridians of the celestial sphere, one of which passes through the poles and the two solstices, the other through the poles and the two equinoxes; hence designated as solstitial colure and equinoxial colure, respectively.
Each solstice is upon the ecliptic midway between the equinoxes, and therefore go from each.
His conclusions may be thus summarized: (r) only stars near the solstitial colure had their maximum north and south positions when the sun was near the equinoxes, (2) each star was at its maximum positions when it passed the zenith at six o'clock morning and evening (this he afterwards showed to be inaccurate, and found the greatest change in declination to be proportional to the latitude of the star), (3) the apparent motions of all stars at about the same time was in the same direction.
To the south of this in Europe the single maximum at mid-winter is replaced by two maxima, somewhere about the equinoxes.
The Scandinavian data, from the wealth of observations, are probably the most representative, and even in the most northern district of Scandinavia the smallness of the excess of the frequencies in December and January over those in March and October suggests that some influence tending to create maxima at the equinoxes has largely counterbalanced the influence of sunlight and twilight in reducing the frequency at these seasons.
These two motions are defined with greater detail in the articles Precession Of The Equinoxes and Nutation.
The precession of the equinoxes is due to the fact that the earth performs a motion of this kind about its centre, and the whole class of such motions has therefore been termed precessional.
The laws of motion of the ecliptic and equator are stated in the article Precession Of The Equinoxes.
These seasons are governed by the apparent movements of the sun, the winters occurring at the equinoxes and the summers at the solstices.
In the other letters written in 1685 and 1686 he applies to Flamsteed for information respecting the orbits of the satellites of Jupiter and Saturn, respecting the rise and fall of the spring and neap tides at the solstices and the equinoxes, respecting the flattening of Jupiter at the poles (which, if certain, he says, would conduce much to the stating the reasons of the precession of the equinoxes), and respecting the difference between the observed places of Saturn and those computed from Kepler's tables about the time of his conjunction with Jupiter.
Already, in the third millennium B.C., equinoxes and solstices were determined in China by means of culminating stars.
Their sidereal year was 4zm too long, s and they kept the ecliptic stationary among the stars, making no allowance for the shifting of the equinoxes.
and cast horoscopes; here Tobit ben Korra (836 901) developed his long unquestioned, yet misleading theory of the " trepidation " of the equinoxes; Abd-ar-rahman al-Safi 9 0 3-9 86) revised at first hand the catalogue of Ptolemy; 3 and Abulwefa (939-998), like al-Safi, a native of Persia, made continuous planetary observations, but did not (as alleged by L.
By these means, employed with consummate skill, he attained an unprecedented degree of accuracy, and as an incidental though valuable result, demonstrated the unreality of the supposed trepidation of the equinoxes.
Gravitation was thus shown to be the sole influence governing the movements of planets and satellites; the figure of the rotating earth was successfully explained by its action on the minuter particles of matter; tides and the precession of the equinoxes proved amenable to reasonings based on the same principle; and it satisfactorily accounted as well for some of the chief lunar and planetary inequalities.
The equinoxes are the two points on the celestial sphere where the ecliptic intersects the celestial equator.
It also acted as an observatory, containing markers that enabled the Inca priests to predict eclipses, solstices and equinoxes (8 ).
The earth's precession leads to the precession of the equinoxes.
Mathematics was far advanced then, that is why ancient Indian sages fixed the rate of precession of Equinoxes accurately.
The key stones are aligned with major major solar and lunar events including solstices and Equinoxes.
Gilded Hornton stone with declination lines crossing the hour lines to mark the summer solstice and equinoxes.
The ecliptic intersects the celestial equator at two opposite points, the equinoxes, at an angle of 23Ã‚° 27'.
Professor Newcomb, who has compiled an instructive table of the equinoxes severally observed by Hipparchus and Ptolemy, with their errors deduced from Leverrier's solar tables, finds palpable evidence that the discrepancies between the two series were artificially reconciled on the basis of a year 6 m too long, adopted by Ptolemy on trust from his predecessor.
The key stones are aligned with major major solar and lunar events including Solstices and Equinoxes.
These are the equinoxes, solstices and cross-quarter days, progressing clockwise from the winter solstice at the top.
These scholars also charted seasonal information regarding the equinoxes and solstices.
The ecliptic intersects the celestial equator at two opposite points, the equinoxes, at an angle of 23° 27'.
In 1749 he furnished a method of applying his principles to the motion of any body of a given figure; and in 1754 he solved the problem of the precession of the equinoxes, determined its quantity and explained the phenomenon of the nutation of the earth's axis.
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