Solar Eclipse Of August Research Articles

Magnetic work of the Dominion Observatory, Canada

A systematic magnetic survey of the whole of the Dominion was the objective of those responsible for the inauguration of magnetic work by the Dominion Observatory in 1907. The point has now been reached in the development of the survey where, owing to the limited personnel available, little can be done beyond reoccupying repeat‐stations for secular change, though a considerable part of the country has not yet been included in the general survey.As reported in 1931, a program of observations at repeat‐stations was begun in 1930. This was continued in 1931, and during the season observations of the three magnetic elements, declination, inclination, and horizontal intensity, were made at 55 stations representing 34 localities. In the region between longitude 60° west and 75° west, and south of latitude 49°, 23 stations were occupied. Of those remaining, which are in western Canada, nine are along the water‐route to the Arctic Ocean between Chipewyan on Lake Athabaska and Arctic Red River on Mackenzie River. With the exception of two new stations, which were occupied at the time of the total solar eclipse in August, no field‐work was done in 1932 owing to lack of funds.

Observations in Transmission during the Solar Eclipse of August 31, 1932

This paper is a report of the result of tests on transmission during the solar eclipse of August 31, 1932. Signals in the 7500-kilocycle band were transmitted from a point in the path of totality and were recorded in Cleveland, Ohio. The records show a slow rise in level until a few minutes before totality when a sharp increase was observed. At totality the signals suddenly dropped to a very low level, then increased slowly until the end of the eclipse, when a second rise in intensity took place. This peak continued for several minutes and then fell to the normal level.

Observations of the Effective Height of the Kennelly-Heaviside Layer and Field Intensity during the Solar Eclipse of August 31, 1932

The result of observations of the effective height of the Kennelly-Heaviside Layer on frequencies of 1640, 3492.5, and 4550 kilocycles are described. On the higher frequencies two height maxima, one before and one after totality, are observed. These maxima occur at approximately 50 per cent totality. Field intensity observations on 6095, 940, and 16.1 kilocycles taken at Tufts College are also described, and a marked eclipse effect is found on the two higher frequencies. The nature of the field intensity variations observed is in good agreement with those anticipated as a result of observations during the eclipse of 1925.

RADIO OBSERVATIONS ON THE UPPER IONIZED LAYER OF THE ATMOSPHERE AT THE TIME OF THE TOTAL SOLAR ECLIPSE OF AUGUST 31, 1932

This report contains the results from one of the three stations set up by the National Research Council of Canada to take observations on radio reflections from the ionized layers in the upper atmosphere during the total solar eclipse of August 31, 1932. The station concerned was located at Kingston, Ontario, and was approximately under the centre of totality for the upper or Appleton layer. Hence observations at this station were limited to the upper layer. The results from the other two stations at Corner Brook, Newfoundland, and at Vankleek Hill, Ontario, are reported in the paper immediately preceding (8).The method was that developed by Breit and Tuve, in which a short pulse is transmitted, the reflection being received and its time delay recorded by means of a cathode ray oscillograph.The results indicate that the ionization of the upper layer is caused by radiation (presumably ultra-violet light) from the sun. Whether or not this is the sole cause is uncertain because of the time lag in recombination of ions in the layer. A reduction in ionization of over 30% was noted.A magnetic storm which occurred a few days before the eclipse made the results more difficult to interpret but gave some information of the effect of such a storm on the upper layer. It appeared to cause considerable instability in the layer and a somewhat lower ion content.

FADING AND SIGNAL-STRENGTH MEASUREMENTS TAKEN DURING THE SOLAR ECLIPSE OF AUGUST 31, 1932

This paper contains the results of observations on signal strength and fading, taken during the total solar eclipse of August 31, 1932, by the Canadian Marconi Company, the Northern Electric Company, the Marine Department of the Canadian Government and l'Ecole Polytechnique, Montreal.The Canadian Marconi Company at Yamachiche took signal-strength observations on trans-Atlantic and American short-wave stations. The Northern Electric Company measured field strengths in Montreal from the Ottawa station in the broadcast band (600 Kc.). The stations of the Marine Department in the Hudson Strait and Hudson Bay regions and also in the Newfoundland and Nova Scotia region took notes on short-wave reception from Ottawa and direction-finding bearings on specified nearby stations. L'Ecole Polytechnique had a receiving station at Rigaud, Quebec.The results of observations on short waves indicate no effect at the time of the predicted corpuscular eclipse, but a definite night effect at the time of optical totality. Direction-finding stations and observations on the broadcast band report no effect.

MEASUREMENTS OF IONIZATION IN THE KENNELLY-HEAVISIDE LAYER DURING THE SOLAR ECLIPSE OF 1932

The ionization of the Kenelly-Heaviside layer was measured by Appleton's method during the total solar eclipse of August 31, 1932. In contrast to normal days, a sudden decrease of 58% during the period of optical totality was found. This is shown to be in accord with Appleton's, but not with Chapman's, theory that the cause of lower layer ionization is ultra-violet light from the sun. Some measurements were made of the effective height of the Appleton layer and these are discussed in detail. There is a marked effect at the time of optical totality on this layer also.

Probability of a Magnetic Storm During the Solar Eclipse of August 31, 1932

Probability of a Magnetic Storm During the Solar Eclipse of August 31, 1932

Probability of a Magnetic Storm During the Solar Eclipse of August 31, 1932

Probability of a Magnetic Storm During the Solar Eclipse of August 31, 1932

Suggested Wireless Observations during the Solar Eclipse of August 31, 1932

AT a recent Geophysical Discussion at the Royal Astronomical Society (an account of which has been published in the March issue of the Observatory) the possibility of deriving information concerning the nature of the solar radiation responsible for upper-atmospheric ionisation by means of wireless observations made during a solar eclipse was discussed by us. It is known that the agents principally responsible for the ionisation in both of the atmospheric ionised layers travel rectilinearly, so that both ultraviolet light and swiftly moving neutral particles may be considered as possible causes. Because of the difference in velocity with which these two types of radiation travel, it turns out that there are important differences in the incidence in time and place for what may be called the ‘optical eclipse’ and the ‘corpuscular eclipse’, when the moon cuts off the solar stream from the earth.

The total solar eclipse of August 31, 1932

The total solar eclipse of August 31, 1932

Proposed International Magnetic and Allied Observations During the Total Solar Eclipse of August 21, 1914 (Civil Date)

Proposed International Magnetic and Allied Observations During the Total Solar Eclipse of August 21, 1914 (Civil Date)

Atmospheric electricity observations at Battle Harbor, Labrador, during the solar eclipse of August 30, 1905

The eclipse party sent to Battle Harbor, Labrador, by the Department of Terrestrial Magnetism of the Carnegie Institution of Washington, in addition to observations of terrestrial magnetism embraced in its program such observations of atmospheric electricity as could be obtained without interfering with its principal work. The time available for this work being thus limited it was decided to observe only potential gradient and specific conductivity. These observations were entrusted to Messrs. Bowen and Homrighaus, members of the party, and it is greatly to their credit that so much was accomplished under the particularly difficult and trying conditions encountered.

RESULTS OF THE SEARCH FOR AN INTERMERCURIAL PLANET AT THE TOTAL SOLAR ECLIPSE OF AUGUST 30, 1905

RESULTS OF THE SEARCH FOR AN INTERMERCURIAL PLANET AT THE TOTAL SOLAR ECLIPSE OF AUGUST 30, 1905

Contribution to the study of the effects produced on the magnetic declination by the total solar eclipse of August 30, 1905

Besides experiments relative to atmospheric electricity of which brief accounts have already been given elsewhere,2 I obtained at Philippeville, Algiers, between August 14 and September 20, 1905, continuous registrations of variations of the magnetic declination and of. the horizontal intensity with the purpose of discovering a possible influence of the eclipse on the usual course of the diurnal variation of these elements. The instruments were installed under excellent conditions inside a casemate where the temperature and the hygrometric conditions were extremely constant, (the daily variation of the temperature there being less than 0.°1C.) The description of the apparatus,3 as well as the details of the results relative to the absolute values of the magnetic elements at the place of observation and to their normal diurnal variation, will be presented in a memoir of the “Annales du Bureau des Longitudes” now in preparation. I will confine myself at present to giving some brief observations as to the results obtained on the day of the eclipse.

Results of the search for an intramercurial planet at the total solar eclipse of August 30, 1905

Results of the search for an intramercurial planet at the total solar eclipse of August 30, 1905

Observations Made with Selenium Cells during the Total Solar Eclipse of August 30, 1905

Observations Made with Selenium Cells during the Total Solar Eclipse of August 30, 1905

Solar Eclipse of August 30, 1905

Solar Eclipse of August 30, 1905

Temperature changes during the partial solar eclipse of august 30, 1905, on the surface and at 3000 ft. at oxshott

Temperature changes during the partial solar eclipse of august 30, 1905, on the surface and at 3000 ft. at oxshott

The Total Solar Eclipse of August 30

IN visiting Spain at the end of August of this year I was actuated by the desire once again, after an interval of twenty-three years, to witness the marvellous and unique phenomenon of a total solar eclipse. It is a sight which cannot be imagined—it must be seen. Happening at a time of maximum sun-spot frequency, it was reasonable to expect a considerable display of protuberances, and I wished to form my own idea of their size by checking their persistence or non-persistence through the phase of mid-totality on a day which otherwise may be taken to have been chosen at random. For this purpose a station on, or very close to, the line of central eclipse was essential. Torreblanca was chosen because it was the station of the Barcelona and Valencia railway which was nearest to the line of central eclipse, lying, in fact, about a mile to the south-west of it.

Magnetic and Allied Observations During the Total Solar Eclipse of August 30, 1905

In addition to the stations as already announced in the previous issues, information was received from General Rykatschew that a magnetic expedition would be sent to Assuan, Egypt, under the auspices of the St. Petersburg Academy of Sciences and under the direction of M. Dubinsky. The stations finally decided upon by the Department Terrestrial Magnetism in order to provide for the proper distribution and successful study of the subject under investigation were as follows: