Solar eclipse of February 25, 1952

Solar eclipse of February 25, 1952
Map
Type of eclipse
Nature	Total
Gamma	0.4697
Magnitude	1.0366
Maximum eclipse
Duration	189 s (3 min 9 s)
Coordinates	15°36′N32°42′E / 15.6°N 32.7°E / 15.6; 32.7
Max. width of band	138 km (86 mi)
Times (UTC)
Greatest eclipse	9:11:35
References
Saros	139 (26 of 71)
Catalog # (SE5000)	9402

A total solar eclipse occurred on February 25, 1952. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of 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. The path of totality crossed Africa, the Middle East, and Asia. ^{[1] [2] [3] [4] [5]}

Observations

Astronomers from various countries started traveling to Khartoum, capital of Anglo-Egyptian Sudan from January 1952. The team of the United States Naval Research Laboratory made studies in radio astronomy, spectrum, luminosity of corona and spectral observations ^[6] . Teams of the High Altitude Observatory of Harvard University and University of Colorado analyzed the spectrum of the Balmer series in the hydrogen spectral series ^[7] . In addition, French astronomer Bernard Ferdinand Lyot, who invented the coronagraph that allows observing the solar corona at any time, not limited to total solar eclipses, died of a heart attack in Cairo, Egypt on his way back from observing the total solar eclipse in Sudan ^[8] .

Related eclipses

Solar eclipses of 1950–1953

This eclipse is a member of a semester series. An eclipse in a semester series of solar eclipses repeats approximately every 177 days and 4 hours (a semester) at alternating nodes of the Moon's orbit. ^[9]

Solar eclipse series sets from 1950 to 1953
Ascending node				Descending node
Saros	Map	Gamma		Saros	Map	Gamma
119	1950 March 18 Annular (non-central)	-0.99880		124	1950 September 12 Total	0.89030
129	1951 March 7 Annular	-0.24196		134	1951 September 1 Annular	0.15570
139	1952 February 25 Total	0.46973		144	1952 August 20 Annular	-0.61023
149	1953 February 14 Partial	1.13308		154	1953 August 9 Partial	-1.34403
Solar eclipse of July 11, 1953 belongs to the next lunar year set.

Saros 139

This eclipse is a member of saros series 139, repeating every 18 years, 11 days, 8 hours, containing 71 events. The series started with partial solar eclipse on May 17, 1501. It contains hybrid eclipses on August 11, 1627, through to December 9, 1825; and total eclipses from December 21, 1843, through to March 26, 2601. The series ends at member 71 as a partial eclipse on July 3, 2763. Its eclipses are tabulated in three columns; every third eclipse in the same column is one exeligmos apart, so they all cast shadows over approximately the same parts of the Earth.

The solar eclipse of June 13, 2132, will be the longest total solar eclipse since July 11, 1991, at 6 minutes, 55.02 seconds.

The longest duration of totality will be produced by member 39 at 7 minutes, 29.22 seconds on July 16, 2186. ^[10] After that date, the durations of totality will decrease until the series ends. This date is the longest solar eclipse computed between 4000 BC and AD 6000. ^[11] Saros series eclipses occur during the Moon's ascending node (a term related to our equator and polar-naming conventions).

Series members 24–45 occur between 1901 and 2300
24	25	26
February 3, 1916	February 14, 1934	February 25, 1952
27	28	29
March 7, 1970	March 18, 1988	March 29, 2006
30	31	32
April 8, 2024	April 20, 2042	April 30, 2060
33	34	35
May 11, 2078	May 22, 2096	June 3, 2114
36	37	38
June 13, 2132	June 25, 2150	July 5, 2168
39	40	41
July 16, 2186	July 27, 2204	August 8, 2222
42	43	44
August 18, 2240	August 29, 2258	September 9, 2276
45
September 20, 2294

Metonic series

The metonic series repeats eclipses every 19 years (6939.69 days), lasting about 5 cycles. Eclipses occur in nearly the same calendar date. In addition, the octon subseries repeats 1/5 of that or every 3.8 years (1387.94 days).

22 eclipse events between December 13, 1898 and July 20, 1982
December 13–14	October 1–2	July 20–21	May 9	February 24–25
111	113	115	117	119
December 13, 1898		July 21, 1906	May 9, 1910	February 25, 1914
121	123	125	127	129
December 14, 1917	October 1, 1921	July 20, 1925	May 9, 1929	February 24, 1933
131	133	135	137	139
December 13, 1936	October 1, 1940	July 20, 1944	May 9, 1948	February 25, 1952
141	143	145	147	149
December 14, 1955	October 2, 1959	July 20, 1963	May 9, 1967	February 25, 1971
151	153	155
December 13, 1974	October 2, 1978	July 20, 1982

Notes

1. "Today's Total Eclipse May Yield New Facts On Sun's Chemistry And Age". The Vancouver News-Herald. Vancouver, British Columbia, Canada. 1952-02-26. p. 4. Retrieved 2023-10-17– via Newspapers.com.
2. "Eclipse Studied in Sudan to Test Einstein's Theory". Richmond Times-Dispatch. Richmond, Virginia. 1952-02-26. p. 15. Retrieved 2023-10-17– via Newspapers.com.
3. "'PERFECT' CONDITIONS FOR TOTAL ECLIPSE OF THE SUN". The Guardian. London, Greater London, England. 1952-02-26. p. 5. Retrieved 2023-10-17– via Newspapers.com.
4. "Scientists View Total Sun Eclipse". The News. Frederick, Maryland. 1952-02-26. p. 1. Retrieved 2023-10-17– via Newspapers.com.
5. "Top Scientists Get Rare Glimpse of Full Eclipse". St. Louis Globe-Democrat. St. Louis, Missouri. 1952-02-26. p. 1. Retrieved 2023-10-17– via Newspapers.com.
6. M. K. Aly (April 1952). "Khartoum expeditions for total solar eclipse of February 25th, 1952". The Observatory. 72: 63–72. Archived from the original on 6 April 2017.
7. Athay, R. G., Billings, D. E., Evans, J. W., & Roberts, W. O. "Emission in Hydrogen Balmer Lines and Continuum in Flash Spectrum of 1952 Total Solar Eclipse at Khartoum, Sudan". The Astrophysical Journal . 120: 94–111. Archived from the original on 6 April 2017.
8. "Bernard Lyot (1897--1952)". Université de Montréal. Archived from the original on 3 March 2016.
9. van Gent, R.H. "Solar- and Lunar-Eclipse Predictions from Antiquity to the Present". A Catalogue of Eclipse Cycles. Utrecht University. Retrieved 6 October 2018.
10. Saros Series Catalog of Solar Eclipses NASA Eclipse Web Site.
11. Ten Millennium Catalog of Long Solar Eclipses, −3999 to [phone] BCE to 6000 CE) Fred Espenak.

References

• Earth visibility chart and eclipse statistics Eclipse Predictions by Fred Espenak, NASA/GSFC
  • Google interactive map
  • Besselian elements
• Solar eclipse of February 25, 1952 in Russia Archived January 3, 2010, at the Wayback Machine