Solar eclipse of January 14, 1926 explained

A total solar eclipse occurred at the Moon's descending node of orbit on Thursday, January 14, 1926,[1] with a magnitude of 1.043. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the Sun for a viewer on Earth. A total solar eclipse occurs when the Moon's apparent diameter is larger than the Sun's, blocking all direct sunlight, turning day into darkness. Totality occurs in a narrow path across Earth's surface, with the partial solar eclipse visible over a surrounding region thousands of kilometres wide. Occurring only about 17 hours after perigee (on January 14, 1926, at 23:30 UTC), the Moon's apparent diameter was larger.[2]

Totality was visible from French Equatorial Africa (the part now belonging to Central African Republic), northeastern Belgian Congo (today's DR Congo), southwestern tip of Anglo-Egyptian Sudan (the part now belonging to South Sudan), British Uganda (today's Uganda), British Kenya (today's Kenya), southern tip of Italian Somaliland (today's Somalia), British Seychelles (today's Seychelles), Dutch East Indies (today's Indonesia), North Borneo (now belonging to Malaysia), and Philippines. A partial eclipse was visible for parts of East Africa, the Middle East, South Asia, Southeast Asia, East Asia, and Australia.

Observations

The event was observed by astronomers, of which several groups gathered in Sumatra, to watch the eclipse. One was from Germany, one was from the Netherlands, and three were from the United States (the Naval Observatory, Sproul Observatory, and the Bureau of Standards). A Reuters correspondent gave the total number of astronomers on Sumatra as 50.

The Dutch expedition, in Palambang, was unable to observe the first phase of the eclipse (due to cloud coverage); the leader of a British expedition in Bencoolen reported that he had "carried out his full program". The Naval Observatory was specifically cited as being set up in Tebing Tinggi, in the southeast of Sumatra. One objective of the observations was to evaluate Albert Einstein's theory of general relativity; cloudy conditions made this difficult. John Miller, head of an expedition from Swarthmore College set up in Bencoolen, is quoted by the Philadelphia Inquirer:

That theory, which was advanced a few years ago to support Newton's law of gravitation, has proved difficult to astronomers, since important data bearing upon it can only be gathered during periods of total eclipse of the Sun. The eclipse in January of last year, which was visible in sections of New England, was also a failure in that respect, since atmospheric conditions were not satisfactory for applying the Einstein theory to the test. Special photographic equipment for gathering data on the theory was taken to Sumatra by the Swarthmore scientists, and four playtes wer made during the eclipse, Dr. Miller cabled.
[...]
"No authentic statement can be made until after the plates have been developed, but we believe that the ten plates exposed in the great 62-foot camera are not seriously affected; the ones in the shorter cameras may be, but it is not likely. We are apprehensive that the four plates exposed in the fifteen-foot twin-camera for the Einstein effect are damaged. The stars surrounding the sun were rather faint and we fear the thin clouds may have blotted the faint stars out. If this is so the Einstein experiment will have failed."
The Swarthmore team had arrived in November 1925, and taken two months to set up the equipment for the observation. Apart from the relativity experiments, other photographs were taken to better understand the composition of the Sun's corona: "Because of the immense distances from the sun's surface which the corona attains, it has been assumed by astronomers that the corona was not composed of gases as are the 'prominences,' seen nearer the surface. What the composition of the corona may be has not been discovered." While the experiments in Sumatra observed the event nearly unobstructed, others in Manila failed completely, on account of cloudy weather. Australian reports from Melbourne confirmed it was visible there.

In popular culture

The eclipse plays a central role in the Call of Cthulhu campaign 'Masks of Nyarlathotep'.

Eclipse details

Shown below are two tables displaying details about this particular solar eclipse. The first table outlines times at which the moon's penumbra or umbra attains the specific parameter, and the second table describes various other parameters pertaining to this eclipse.[3]

January 14, 1926 Solar Eclipse Times! Event! Time (UTC)
First Penumbral External Contact1926 January 14 at 03:59:05.5 UTC
First Umbral External Contact1926 January 14 at 04:54:54.7 UTC
First Central Line1926 January 14 at 04:55:36.5 UTC
First Umbral Internal Contact1926 January 14 at 04:56:18.3 UTC
First Penumbral Internal Contact1926 January 14 at 05:53:59.2 UTC
Ecliptic Conjunction1926 January 14 at 06:34:55.9 UTC
Greatest Duration1926 January 14 at 06:36:14.0 UTC
Greatest Eclipse1926 January 14 at 06:36:57.7 UTC
Equatorial Conjunction1926 January 14 at 06:38:24.8 UTC
Last Penumbral Internal Contact1926 January 14 at 07:19:54.3 UTC
Last Umbral Internal Contact1926 January 14 at 08:17:34.9 UTC
Last Central Line1926 January 14 at 08:18:17.6 UTC
Last Umbral External Contact1926 January 14 at 08:19:00.3 UTC
Last Penumbral External Contact1926 January 14 at 09:14:47.1 UTC
January 14, 1926 Solar Eclipse Parameters! Parameter! Value
Eclipse Magnitude1.04305
Eclipse Obscuration1.08795
Gamma0.19725
Sun Right Ascension19h40m49.1s
Sun Declination-21°25'36.6"
Sun Semi-Diameter16'15.6"
Sun Equatorial Horizontal Parallax08.9"
Moon Right Ascension19h40m45.4s
Moon Declination-21°13'35.8"
Moon Semi-Diameter16'40.7"
Moon Equatorial Horizontal Parallax1°01'12.6"
ΔT23.9 s

Eclipse season

See also: Eclipse cycle. This eclipse is part of an eclipse season, a period, roughly every six months, when eclipses occur. Only two (or occasionally three) eclipse seasons occur each year, and each season lasts about 35 days and repeats just short of six months (173 days) later; thus two full eclipse seasons always occur each year. Either two or three eclipses happen each eclipse season. In the sequence below, each eclipse is separated by a fortnight.

Related eclipses

Eclipses in 1926

Metonic

Tzolkinex

Half-Saros

Tritos

Solar Saros 130

Inex

Triad

Inex series

References

Notes and References

  1. Web site: January 14, 1926 Total Solar Eclipse. timeanddate. 3 August 2024.
  2. Web site: Moon Distances for London, United Kingdom, England. timeanddate. 3 August 2024.
  3. Web site: Total Solar Eclipse of 1926 Jan 14. EclipseWise.com. 3 August 2024.