scholarly journals VII. Note on 'spectroscopic papers'

1879 ◽  
Vol 29 (196-199) ◽  
pp. 166-168

In a recent communication to the Royal Society, Mr. Lockyer has criticised our statement of Young’s wave-length identifications of certain chromospheric lines. As to the wave-length, we have throughout our table omitted all figures after the decimal point merely for the sake of not cumbering the table. The numbers, Young tells us, are not his own, but taken from Ǻngström’s catalogue. Moreover, as to Young’s identifications with metallic lines, he states expressly that they were taken from the maps of Kirchhoff, Ǻngström, and Thalén, and Watts’s “Index of Spectra.” But our object was not to criticise Young’s work, but only to use it for the purpose of comparing the behaviour of certain metals on the earth and in the sun, and the conditions under which certain lines appear, or do not appear, or are reversed.

1765 ◽  
Vol 55 ◽  
pp. 326-344 ◽  

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".


2020 ◽  
Author(s):  
Mark Zilberman

The hypothetical “Dimming Effect” describes the change of the number of photons arriving from a moving light source per unit of time. In non-relativistic systems, the “Dimming effect” may occur due to the growing distance of light sources moving away from the receiver. This means that due to the growing distance, the photons continuously require more time to reach the receiver, which reduces the number of received photons per time unit compared to the number of emitted photons. Understandably, the proposed “Dimming effect” must be tested (confirmed or rejected) through observations. a. This article provides the formula for the calculation of “Dimming effect” values using the redshift parameter Z widely used in astronomy. b. The “Dimming effect” can possibly be detected utilizing the orbital movement of the Earth around the Sun. In accordance to the “Dimming effect”, observers on Earth will view 1.0001 more photons per time unit emitted by stars located near the ecliptic plane in the direction of the Earth orbiting the Sun. And, in contrast, observers will view only 0.9999 photons per time unit emitted by stars located near the ecliptic plane in the direction opposite to the Earth orbiting the Sun. Calculating precise measurements of the same stars within a 6-month period can possibly detect this difference. These changes in brightness are not only for specific stars, as the change in brightness takes place for all stars near the ecliptic in the direction of the Earth’s orbit around the Sun and in the opposite direction. c. The “Dimming effect” can possibly be detected in a physics laboratory using a moving light source (or mirror) and photon counters located in the direction of travel and in the opposite direction. d. In theory, Dilation of time can also be used for testing the existence of the “Dimming effect.” However, in experiments on Earth this effect appears in only the 14th digit after the decimal point and testing does not appear to be feasible. e. Why is it important to test the “Dimming effect?” If confirmed, it would allow astronomers to adjust values of "Standard Candles" used in astronomy. Since “Standard Candles” are critical in various cosmological models, the “Dimming effect” can correct models and/or reveal and support new models. If it is proved that the “Dimming effect” does not exist, it will mean that the number of photons arriving per unit of time does not depend on the speed of the light source and observer, which is not so apparent.


A little over two hundred years ago a number of serious and learned men in Copenhagen, London, Paris, St Petersbourg, Stockholm and elsewhere, men who were academicians, Fellows of the Royal Society, Lords of the Admiralty, politicians and the like, had been thinking seriously and learnedly about the behaviour of Venus, not, of course, about Venus as represented coldly and chastely by the marble statues being imported from Italy or more warmly in the paintings of Boucher and his contemporaries, but about her far distant planet which was calculated to pass across the disk of the Sun in 1769 and not to make another such transit until 1874. Observations of the 1769 transit at widely separated stations would provide, it was hoped, the means of calculating the distance of the Earth from the Sun. The Royal Society in London, having set up in November 1767 a sub-committee ‘to consider the places proper to observe the coming Transit of Venus’ and other particulars relevant to the same, presented a memorial to King George III outlining possible benefits to science and navigation from observations made in the Pacific Ocean and received in return the promise of £4000 and a suitable ship provided by the Royal Navy (8).


1960 ◽  
Vol 13 (4) ◽  
pp. 365-382
Author(s):  
Harold Spencer Jones

This year the Royal Society celebrates the third centenary of its foundation. In this paper Sir Harold Spencer Jones, the late Astronomer Royal, who was the Institute's first President, describes the early years of the Society and shows how closely some of its work was related to navigation.For some two thousand years, until well into the seventeenth century, the writings of the ancient Greek philosophers, and in particular those of Aristotle, were regarded as the supreme fountain of wisdom and the source of all knowledge. The break with the Aristotelian dogma may be said to have started with the publication by Copernicus in 1543 of his De Revolutionibus Orbium Coelestium whereby the Earth was displaced from proud position as the centre of the Universe, fixed and immovable, and asserted to be not only rotating around an axis but also to be merely one of a system of planets revolving around the Sun as a centre. Copernicus had refrained for thirty years from publishing his theory as he knew that it would be received with ridicule, not merely because it was not in accordance with Aristotelian dogma but also because it would be held to be against the Scriptures. The Copernican theory met, in fact, with widespread opposition and more than a century elapsed before it came to be generally accepted; for long it was regarded as merely a convenient mathematical representation of the motions of the planets without any true physical basis.


2020 ◽  
Author(s):  
M. Zilberman

Abstract The hypothetical “Dimming Effect” describes the change of the number of photons arriving from a moving light source per unit of time. In non-relativistic systems, the “Dimming effect” may occur due to the growing distance of light sources moving away from the receiver. This means that due to the growing distance, the photons continuously require more time to reach the receiver, which reduces the number of received photons per time unit compared to the number of emitted photons.Understandably, the proposed “Dimming effect” must be tested (confirmed or rejected) through observations.a. This article provides the formula for the calculation of “Dimming effect” values using the redshift parameter Z widely used in astronomy.b. The “Dimming effect” can possibly be detected utilizing the orbital movement of the Earth around the Sun. In accordance to the “Dimming effect”, observers on Earth will view 1.0001 more photons per time unit emitted by stars located near the ecliptic plane in the direction of the Earth orbiting the Sun. And, in contrast, observers will view only 0.9999 photons per time unit emitted by stars located near the ecliptic plane in the direction opposite to the Earth orbiting the Sun. Calculating precise measurements of the same stars within a 6-month period can possibly detect this difference. These changes in brightness are not only for specific stars, as the change in brightness takes place for all stars near the ecliptic in the direction of the Earth’s orbit around the Sun and in the opposite direction.c. The “Dimming effect” can possibly be detected in a physics laboratory using a moving light source (or mirror) and photon counters located in the direction of travel and in the opposite direction.d. In theory, Dilation of time can also be used for testing the existence of the “Dimming effect.” However, in experiments on Earth this effect appears in only the 14th digit after the decimal point and testing does not appear to be feasible.e. Why is it important to test the “Dimming effect?”* If confirmed, it would allow astronomers to adjust values of "Standard Candles" used in astronomy. Since “Standard Candles” are critical in various cosmological models, the “Dimming effect” can correct models and/or reveal and support new models.* If it is proved that the “Dimming effect” does not exist, it will mean that the number of photons arriving per unit of time does not depend on the speed of the light source and observer, which is not so apparent.


Author(s):  
A. Cook

Fellows of The Royal Society have been concerned with the definition and measurement of time from the first days of the Society. John Flamsteed, F.R.S., ‘Royal Astronomer’, showed that the rotation of the Earth was isochronous and that the length of the solar day varied with the season because the path of the Earth about the Sun was an ellipse inclined to the Equator of the Earth. In the 20th century, D.W. Dye, F.R.S., made quartz oscillators that replaced mechanical clocks, and L. Essen, F.R.S., brought into use at the National Physical Laboratory the first caesium beam frequency standard and advocated that atomic time should replace astronomical time as the standard. The Society supported the development of chronometers for use at sea to determine longitude, and Fellows used the electric telegraph to find longitude in India. Edmond Halley, F.R.S., estimated the age of the Earth from the saltiness of lakes and seas; Lord Kelvin, F.R.S., estimated the rate at which energy was being radiated from the Sun; and Lord Rutherford, F.R.S., showed how the ages of rocks and of the Earth could be found from decay of radioactive minerals in them.


1997 ◽  
Vol 161 ◽  
pp. 761-776 ◽  
Author(s):  
Claudio Maccone

AbstractSETI from space is currently envisaged in three ways: i) by large space antennas orbiting the Earth that could be used for both VLBI and SETI (VSOP and RadioAstron missions), ii) by a radiotelescope inside the Saha far side Moon crater and an Earth-link antenna on the Mare Smythii near side plain. Such SETIMOON mission would require no astronaut work since a Tether, deployed in Moon orbit until the two antennas landed softly, would also be the cable connecting them. Alternatively, a data relay satellite orbiting the Earth-Moon Lagrangian pointL2would avoid the Earthlink antenna, iii) by a large space antenna put at the foci of the Sun gravitational lens: 1) for electromagnetic waves, the minimal focal distance is 550 Astronomical Units (AU) or 14 times beyond Pluto. One could use the huge radio magnifications of sources aligned to the Sun and spacecraft; 2) for gravitational waves and neutrinos, the focus lies between 22.45 and 29.59 AU (Uranus and Neptune orbits), with a flight time of less than 30 years. Two new space missions, of SETI interest if ET’s use neutrinos for communications, are proposed.


2019 ◽  
Vol 15 (1) ◽  
pp. 73-77
Author(s):  
Valentina V. Ukraintseva ◽  
Keyword(s):  
The Sun ◽  

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