scholarly journals On a method of comparing the light of the Sun with that of the fixed stars

1833 ◽  
Vol 2 ◽  
pp. 355-355
Keyword(s):  
Full Moon ◽  
Angular Distance ◽  
The Other ◽  
The Sun ◽  
Proper Distance ◽  
The Earth ◽  
Direct Light ◽  
Glass Bulb ◽  
The Mean ◽  
Made In

In the Philosophical Transactions for the year 1767, a suggestion is thrown out by Mr. Michell, that a comparison between the light received from the sun and any of the fixed stars, might furnish data for estimating their relative distances; but no such direct comparison had been attempted. Dr. Wollaston was led to infer from some observations that he made in the year 1799, that the direct light of the sun is about one million times more intense than that of the full moon, and therefore very many million times greater than that of all the fixed stars taken collectively. In order to compare the light of the sun with that of a star, he took, as an intermediate object of comparison, the light of a candle reflected from a small bulb, about a quarter of an inch in diameter, filled with quicksilver, and seen, by one eye, through a lens of two inches focus, at the same time that the star or the sun’s image, placed at a proper distance, was viewed by the other eye through a telescope. The mean of various trials seemed to show that the light of Sirius is equal to that of the sun seen in a glass bulb one tenth of an inch in diameter, at the distance of 210 feet, or that they are in the proportion of one to ten thousand millions; but as nearly one half of the light is lost by reflection, the real proportion between the light from Sirius and the sun is not greater than that of one to twenty thousand millions. If the annual parallax of Sirius be half a second, corresponding to a distance of 525,481 times that of the sun from the earth, its diameter would be 3⋅7 times that of the sun, and its light 13⋅8 times as great. The distance at which the sun would require to be viewed, so that its brightness might be only equal to that of Sirius, would be 141,421 times its present distance; and if still in the ecliptic, its annual parallax in longitude would be nearly 3″; but if situated at the same angular distance from the ecliptic as Sirius is, it would have an annual parallax, in latitude, of 1″⋅8.

Precambrian glaciations and the evolution of the atmosphere

1994 ◽  
Vol 12 (7) ◽  
pp. 674-682 ◽  
Author(s):  
J. H. Carver ◽  
I. M. Vardavas
Keyword(s):  
Simple Model ◽  
Land Surface ◽  
Life Forms ◽  
The Other ◽  
The Sun ◽  
Before Present ◽  
Early Proterozoic ◽  
Late Proterozoic ◽  
The Earth ◽  
The Mean

Abstract. Precambrian glaciations appear to be confined to two periods, one in the early Proterozoic between 2.5 and 2 Gyears BP (Before Present) and the other in the late Proterozoic between 1 and 0.57 Gyear BP. Possible reasons for these broad features of the Precambrian climate have been investigated using a simple model for the mean surface temperature of the Earth that partially compensates for the evolution of the Sun by variations in the atmospheric CO2 content caused by outgassing, the formation of continents and the weathering of the Earth's land surface. It is shown that the model can explain the main changes in the Precambrian climate if the early Proterozoic glaciations were caused by a major episode of continental land building commencing about 3 Gyears BP while the late Proterozoic glaciations resulted from biologicallyenhanced weathering of the land surface due to the proliferation of life forms in the transition from the Proterozoic to the Phanerozoic that began about 1 Gyear BP.

scholarly journals The Radiation Integrator in Vacuo, an Instrument for the study of Radiant Heat received from the Sun

1926 ◽  
Vol 25 (3) ◽  
pp. 285-294 ◽  
Author(s):  
P. A. Buxton
Keyword(s):  
Solar Radiation ◽  
Seasonal Changes ◽  
Radiant Heat ◽  
The Other ◽  
The Sun ◽  
The Earth ◽  
The Mean

The “Radiation Integrator in Vacuo” is an instrument designed by a biologist, to assist in the study of solar radiation, as received on the surface of the earth. The principle of the instrument is that a black bulb in vacuo is exposed to the sun's rays; the bulb, which contains alcohol, is connected to a graduated stem maintained at shade temperature; radiant heat from the sun causes alcohol to distil over the bulb into the stem where its volume is measured. In Samoa the shade temperature is practically constant throughout the year, but one believes on theoretical grounds that more radiation is received from the sun between September and March than at the other season, and that the radiation has two maxima, in October and February. This instrument, which has been observed for 12 months, confirms the expectation. The daily mean distillate, the distillate per hour of sunshine (Campbell Stokes) and the mean distillate for the three hours before noon, all show the same seasonal changes.The instrument has been standardized against Gorczynski's pyrheliometer, so that the readings in c.c. of alcohol can be converted into calories. The instrument is not difficult to make or read, and it can be left in the open in all weathers. It integrates its results and requires to be read once a day in Samoa.

A comparison of the changes of magnetic intensity throughout the day in the dipping and horizontal needles, at Treurenburgh Bay in Spitsbergen

1833 ◽  
Vol 2 ◽  
pp. 344-345
Keyword(s):  
Diurnal Variation ◽  
Relative Position ◽  
The Other ◽  
Diurnal Changes ◽  
The Sun ◽  
Magnetic Intensity ◽  
The Earth ◽  
The One ◽  
Rotatory Motion ◽  
Made In

The observations made by the author at Port Bowen in 1825, on the diurnal changes of magnetic intensity taking place in the dipping- and horizontal-needles, appeared to indicate a rotatory motion of the polarizing axis of the earth, depending on the relative position of the sun, as the cause of these changes. By Capt. Foster’s remaining at Spitzbergen, during the late Northern Voyage of Discovery, a favourable opportunity was afforded him of prosecuting this inquiry. Instead of making observations with a single needle, variously suspended, as had been done at Port Bowen, two were employed,— the one adjusted as a dipping-needle, and the other suspended horizontally. The relation between the simultaneous intensities of the two needles could thus be ascertained, and inferences deduced relative to the question whether a diurnal variation in the dip existed as one of the causes of the observed phenomena, or whether, the dip remaining constant, they were occasioned by a change in the intensity. The dipping-needle used was one belonging to the Board of Longitude, and made by Dollond. Both this and the horizontal-needle were made in the form of parallelopipedons, each 6 inches long, 0·4 broad, and 0·05 thick. The experiments were continued from the 30th of July to the 9th of August; and were so arranged, that in the course of two days an observation was made every hour in the four-and-twenty; that is, part of them in one day and another part in the other day.

scholarly journals III. On the nature and construction of the sun and fixed stars

1795 ◽  
Vol 85 ◽  
pp. 46-72 ◽  
Keyword(s):  
Central Body ◽  
Planetary System ◽  
Considerable Progress ◽  
The Sun ◽  
Great Satisfaction ◽  
The Earth ◽  
The World ◽  
Celestial Bodies ◽  
The Universe ◽  
Made In

Among the celestial bodies the sun is certainly the first which should attract our notice. It is a fountain of light that illuminates the world! it is the cause of that heat which main­tains the productive power of nature, and makes the earth a fit habitation for man! it is the central body of the planetary system; and what renders a knowledge of its nature still more interesting to us is, that the numberless stars which compose the universe, appear, by the strictest analogy, to be similar bodies. Their innate light is so intense, that it reaches the eye of the observer from the remotest regions of space, and forcibly claims his notice. Now, if we are convinced that an inquiry into the nature and properties of the sun is highly worthy of our notice, we may also with great satisfaction reflect on the considerable progress that has already been made in our knowledge of this eminent body. It would require a long detail to enumerate all the various discoveries which have been made on this subject; I shall, therefore, content myself with giving only the most capital of them.

scholarly journals XXXIV. On the transit of Venus in 1769. To the Right Honourable The Earl of Morton, President to the Council and Fellows of the Royal Society, this discourse is, with all humility, inscribed, by their humble servant, Thomas Hornsby

1765 ◽  
Vol 55 ◽  
pp. 326-344 ◽  
Keyword(s):  
Royal Society ◽  
The Sun ◽  
The Real ◽  
The Earth ◽  
Theory Of Gravity ◽  
The Right ◽  
Made In

The observations of the late transit of Venus, though made with all possible care and accuracy, have not enabled us to determine with certainty the real quantity of the sun's parallax; since, by a comparison of the observations made in several parts of the globe, the sun's parallax is not less than 8" 1/2, nor does it seem to exceed 10". From the labours of those gentlemen, who have attempted to deduce this quantity from the theory of gravity, it should seem that the earth performs its annual revolution round the sun at a greater distance than is generally imagined: since Mr. Professor Stewart has determined the sun's parallax to be only 6', 9, and Mr. Mayer, the late celebrated Professor at Gottingen, who hath brought the lunar tables to a degree of perfection almost unexpected, is of opinion that it cannot exceed 8".

scholarly journals XXXIV. Observations on the transit of Ve­nus, June the 6th, 1761, made in Spital-Square; the longitude of which is 4' 11" west of the Royal Observatory at Green­wich, and the latitude 51° 31' 15" north

1761 ◽  
Vol 52 ◽  
pp. 182-183
Keyword(s):  
The Sun ◽  
Royal Observatory ◽  
The Mean ◽  
The Difference ◽  
Made In

Having measured the diameter of Venus, on the sun, three times, with the object-glass micrometer, the mean was found to be 58 seconds; and but 6/10 of a second, the difference of the extremes.

scholarly journals Lunar

JOGED ◽  
2017 ◽  
Vol 7 (2) ◽  
Author(s):  
Dewi Sinta Fajawati
Keyword(s):  
Full Moon ◽  
Big Bang ◽  
The Other ◽  
The Sun ◽  
The Moon ◽  
Big Bang Theory ◽  
Essential Idea ◽  
Visual Reaction ◽  
Night Sky ◽  
The One

Bulan merupakan sumber inspiratif dalam penggarapan karya tari ini. Secara ilmu pengetahuan, Bulan adalah benda langit yang disebut satelit, satelit satu-satunya yang dimiliki Bumi dan tercipta secara alami. Banyak teori yang mengatakan tentang terbentuknya Bulan, salah satunya adalah teori Big bang atau dentuman besar. Pada dasarnya Bulan hanyalah sebuah Benda besar berbentuk bulat yang tidak bisa bercahaya, cahaya yang kita lihat pada malam hari merupakan refleksi dari cahaya matahari. Akan tetapi keindahannya memang tidak bisa dipungkiri, karena dia paling bercahaya diantara hamparan langit yang gelap. Cahayanya tidak selalu terang, bahkan tidak selalu bulat, terkadang hanya terlihat setengah atau terlihat seperti sabit..            Penata tari memetaforakan objek bulan yang berada di tempat yang sangat tinggi sebagai sebuah cita-cita yang ingin dicapai. Seringkali lagu anak-anak yang menjadi pengalaman auditif penata tari, menjadikan bulan sebagai objek yang ingin digapai, misal lagu ‘Ambilkan Bulan Bu’. Namun intisari yang akan dipakai dalam penggarapan koregrafinya adalah tentang fase bulan yang tercipta. Bersumber dari rangsang awal melihat bulan atau rangsang visual, penata tari menginterpretasikan fase-fase bulan yang terjadi sebagai fase kehidupan yang dijalani untuk menggapai sebuah cita-cita tersebut.            Koreografi diwujudkan dalam bentuk kelompok dengan membagi dua karate penari. Delapan penari merupakan simbolisasi Bulan, dan satu penari sebagai manusia yang bercita-cita. Dengan bentuk tari dramatik, penyajiannya dibagi menjadi 5 adegan, yaitu Introduksi Big bang, Adegan 1 Moon happen, Adegan 2 Mengejar Impian, Adegan 3 Dancing with Moon, dan Ending ‘Catch Your Dream’. The moon is the essential inspirations of this choreograph. Theoretically, the moon is a sky object which is called as satellite. The one and only naturally created satellite belongs to the planet Earth. There are many theories that explain how the moon was created. One of those theories is Big Bang theory or massive crash. Basically, the moon is just a huge circle thing which is unable to shine its glow. The light that we experience in the evening is the reflection of the sun. However, thebeauty of the moonlight is undeniable as it has the significant light within the darkest night sky. Its light is not always the strongest, even it’s not always circle (full), every so often it is seemed only the half part of it or crescent moon.            The choreographer interpreted the moon that belongs in the highest as the goals that she wants to reach. Most of the time, the children songs (lullaby) that pick the moon as the main object that is desired to be reached, for example the song “Ambilkan Bulan, Bu”. The essential idea that is explored in this choreograph is the creational phase of the moon itself. It was started by way of visual reaction when the choreographer observed the moon, she interpret the moon’s phases as the phases in human’s life which are gone through to reaching their goals. Fall and recovery, passionate, and even sometimes they give it in, are interpreted from the moonlight. The full moon which has the brightest and the most perfect light is likened as the strong spirit. The crescent moon with its soft light is interpreted as low spirit and unconfident.             This in-group-choreograph is separated into two characters with 8 female dancers that are the symbolization of the moon and the other one female dancer symbolizes a human with aspire. With dramatic dance form, this choreograph is presented into five parts, including introduction part of Big Bang, Moon Happen in part one, Chasing Dream is part two, Dancing With The Moon in part three, Catch Your Dream in the ending part.

Decapitated Lunar Goddesses in Aztec Art, Myth, and Ritual

1997 ◽  
Vol 8 (2) ◽  
pp. 185-206 ◽  
Author(s):  
Susan Milbrath
Keyword(s):  
Solar Eclipse ◽  
Seasonal Cycle ◽  
Full Moon ◽  
The Sun ◽  
The Moon ◽  
Seasonal Transition ◽  
The Earth ◽  
New Moon ◽  
The Demonic

AbstractAztec images of decapitated goddesses link the symbolism of astronomy with politics and the seasonal cycle. Rituals reenacting decapitation may refer to lunar events in the context of a solar calendar, providing evidence of a luni-solar calendar. Decapitation imagery also involves metaphors expressing the rivalry between the cults of the sun and the moon. Huitzilopochtli's decapitation of Coyolxauhqui can be interpreted as a symbol of political conquest linked to the triumph of the sun over the moon. Analysis of Coyolxauhqui's imagery and mythology indicates that she represents the full moon eclipsed by the sun. Details of the decapitation myth indicate specific links with seasonal transition and events taking place at dawn and at midnight. Other decapitated goddesses, often referred to as earth goddesses with “lunar connections,” belong to a complex of lunar deities representing the moon within the earth (the new moon). Cihuacoatl, a goddess of the new moon, takes on threatening quality when she assumes the form of a tzitzimime attacking the sun during a solar eclipse. The demonic new moon was greatly feared, for it could cause an eternal solar eclipse bringing the Aztec world to an end.

Solar Motion and Lunar Eclipses in Philolaus’ Cosmological System

Apeiron ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Dirk L. Couprie
Keyword(s):  
The Other ◽  
The Sun ◽  
The Moon ◽  
Internal Logic ◽  
Wrong Side ◽  
The Earth ◽  
Solar Motion ◽  
Length Of The Day

Abstract In this paper, three problems that have hardly been noticed or even gone unnoticed in the available literature in the cosmology of Philolaus are addressed. They have to do with the interrelationships of the orbits of the Earth, the Sun, and the Moon around the Central Fire and all three of them constitute potentially insurmountable obstacles within the context of the Philolaic system. The first difficulty is Werner Ekschmitt’s claim that the Philolaic system cannot account for the length of the day (νυχϑήμερον). It is shown that this problem can be solved with the help of the distinction between the synodic day and the sidereal day. The other two problems discussed in this paper are concerned with two hitherto unnoticed deficiencies in the explanation of lunar eclipses in the Philolaic system. The Philolaic system cannot account for long-lasting lunar eclipses and according to the internal logic of the system, during lunar eclipses the Moon enters the shadow of the Earth from the wrong side. It is almost unbelievable that nobody, from the Pythagoreans themselves up to recent authors, has noticed these two serious deficiencies, and especially the latter, in the cosmology of Philolaus the Pythagorean.

scholarly journals I. On the absolute expansion of mercury

1912 ◽  
Vol 211 (471-483) ◽  
pp. 1-32 ◽  
Keyword(s):  
Hydrostatic Method ◽  
Physical Problems ◽  
Glass Bulb ◽  
Different Temperatures ◽  
The Mean ◽  
The Absolute ◽  
Made In

The determination of the expansion of mercury by the absolute or hydrostatic method of balancing two vertical columns maintained at different temperatures does not appear to have been seriously attempted since the time of Regnault (‘Mém. de l’Acad. Roy. des Sci. de l’Institut de France,' tome I., Paris, 1847). His results, though doubtless as perfect as the methods and apparatus available in his time would permit, left a much greater margin of uncertainty than is admissible at the present time in many cases to which they have been applied. The order of uncertainty may be illustrated by comparing the value of the fundamental coefficient of expansion (the mean coefficient between 0° and 100°C.) given by Regnault himself, with the values since deduced from his observations by Wüllner and by Broch. They are as follows:— Regnault . . . . . . 0·00018153. Wüllner . . . . . . 0·00018253. Broch . . . . . . . 0·00018216. The discrepancy amounts to 1 in 180 even at this temperature, and would be equivalent to an uncertainty of about 4 per cent, in the expansion of a glass bulb determined with mercury by the weight thermometer method. The uncertainty of the mean coefficient is naturally greater at higher temperatures. If, in place of the mean coefficient, we take the actual coefficient at any temperature, the various reductions of Regnault’s work are still more discordant, and the rate of variation of the coefficient with temperature, which is nearly as important as the value of the mean coefficient itself in certain physical problems, becomes so uncertain that the discrepancies often exceed the value of the correction sought. It is only fair to Regnault to say that these discrepancies arise to some extent from the various assumptions made in reducing his results, and are not altogether inherent in the observations themselves.

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