scholarly journals The light of the night sky: Analysis of intensity variations observed at the Cape, at Canberra and in England

1930 ◽  
Vol 126 (801) ◽  
pp. 246-259 ◽  
Keyword(s):  
Diurnal Variation ◽  
Annual Variation ◽  
Period Variation ◽  
The Sun ◽  
Present Communication ◽  
Long Period ◽  
Cape Of Good Hope ◽  
Period 2 ◽  
Royal Observatory ◽  
Night Sky

The purpose of the present communication is primarily to analyse the observations of the light of the night sky secured at the Royal Observatory, Cape of Good Hope, with a visual photometer designed and supplied by Lord Rayleigh, and to discuss the variations in the observed brightness in connection with the variations given by observations elsewhere. In a series of communications to the Society, Rayleigh has found evidence for the following variations :— (1) A long-period variation, which is suspected to be related to the sun-spot period. (2) An annual variation. (3) A variation through the night (diurnal variation).

III. Extract of a letter from Professor Langberg of Christiania to Colonel Sabine, dated June 10th, 1855. Communicated by Colonel Sabine, V. P. and Treas. R. S

1856 ◽  
Vol 7 ◽  
pp. 434-436
Keyword(s):  
Diurnal Variation ◽  
Annual Variation ◽  
The Sun ◽  
The Earth ◽  
British Colonial ◽  
Enormous Quantity ◽  
June 10Th

“Of all the important results from the discussions of the British Colonial Observatory, the discovery of the direct action of the sun on the magnetism of the earth is certainly a fact of the highest interest, in opening quite a new field for investigation; and few modern discoveries in this branch of science have interested me more than yours of the annual variation of the diurnal variation of declination. It seems that M. Secchi of Rome has nearly touched at the same discovery, and I am indeed glad that the enormous quantity of calculations, which you are superintending, did not prevent you from publishing your results before the ripening fruit was plucked by another.

Geomagnetic observations at Halley Bay

1960 ◽  
Vol 256 (1285) ◽  
pp. 219-221 ◽  
Keyword(s):  
Diurnal Variation ◽  
Geomagnetic Activity ◽  
Annual Variation ◽  
The Sun ◽  
Annual Change ◽  
Line Current ◽  
The Difference ◽  
June July ◽  
Geomagnetic Observations

(1) The annual variation of geomagnetic activity is described on the basis of monthly mean K -indices for three selections of days according to activity. (2) The difference between the diurnal variation of geomagnetic activity, as defined by K -indices, in June and December is shown to be due to a universal effect accounted for by the annual change in the diurnal variation of the angle between the earth’s geomagnetic axis and the line joining the sun and earth. (3) The observed field changes in winter (May, June, July) are interpreted as being due to a disturbing line current in the ionosphere; the diurnal variation and movement of this current are described.

Discussion following the presentation by F. Deubner

1977 ◽  
Vol 36 ◽  
pp. 69-74
Keyword(s):  
List Type ◽  
The Sun ◽  
Type Number ◽  
Harmonic Motion ◽  
Locally Excited ◽  
Long Period ◽  
Coherent Wave ◽  
Short Period ◽  
Global Modes

The discussion was separated into 3 different topics according to the separation made by the reviewer between the different periods of waves observed in the sun :1) global modes (long period oscillations) with predominantly radial harmonic motion.2) modes with large coherent - wave systems but not necessarily global excitation (300 s oscillation).3) locally excited - short period waves.

scholarly journals I.—Secular Earth-Creep

1909 ◽  
Vol 6 (4) ◽  
pp. 145-148 ◽  
Author(s):  
E. H. L. Schwarz
Keyword(s):  
South Africa ◽  
Diurnal Variation ◽  
Royal Society ◽  
The Sun ◽  
Special Design ◽  
Important Paper ◽  
Preliminary Results ◽  
Gravitational Pull ◽  
Set Up ◽  
Horizontal Pendulum

Dr. J. R. Sutton has recently read a most important paper to the Royal Society of South Africa on the diurnal variation of level at Kimberley. The paper gave the preliminary results of observations made during the course of three years upon the variation of the level of the ground as recorded by a large horizontal pendulum of a special design made for the author by the Cambridge Instrument Company. It appeared from the results that the movements in the surface of the ground, which set up corresponding movements in the pendulum, were very great. The maximum westerly elongation of the extremity of the pendulum occurred about 5.30 a.m., the maximum easterly about 4.15 p.m., the medium positions a little before 11 a.m. and 9.30 p.m. Geometrically these movements may be represented on the hypothesis that the hemisphere facing the sun bulges out, forming a sort of meniscus to the geosphere. The rise and fall of the surface of the ground which such a supposition would postulate is enormous, and the very magnitude has led Dr. Sutton to hesitate in giving the figures. There can, however, be very little doubt that some rise and fall in the earth's surface is occasioned by the sun's gravitational pull, although the present figures may have to be lessened by taking into consideration other causes which contribute to the disturbance of the pendulum.

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.

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