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Solar eclipse of August 11, 1961

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Solar eclipse of August 11, 1961
Map
Type of eclipse
NatureAnnular
Gamma−0.8859
Magnitude0.9375
Maximum eclipse
Duration395 s (6 min 35 s)
Coordinates45°48′S 4°00′E / 45.8°S 4°E / -45.8; 4
Max. width of band499 km (310 mi)
Times (UTC)
Greatest eclipse10:46:47
References
Saros125 (51 of 73)
Catalog # (SE5000)9423

An annular solar eclipse occurred at the Moon's ascending node of orbit on Friday, August 11, 1961,[1] with a magnitude of 0.9375. 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. An annular solar eclipse occurs when the Moon's apparent diameter is smaller than the Sun's, blocking most of the Sun's light and causing the Sun to look like an annulus (ring). An annular eclipse appears as a partial eclipse over a region of the Earth thousands of kilometres wide. Occurring about 7 hours after apogee (on August 11, 1961, at 17:50 UTC), the Moon's apparent diameter was smaller.[2]

Annularity was visible from a part of Antarctica. A partial eclipse was visible for parts of eastern South America, Southern Africa, and Antarctica.

Eclipse details

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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]

August 11, 1961 Solar Eclipse Times
Event Time (UTC)
First Penumbral External Contact 1961 August 11 at 08:13:26.2 UTC
First Umbral External Contact 1961 August 11 at 09:47:06.3 UTC
First Central Line 1961 August 11 at 09:52:11.0 UTC
First Umbral Internal Contact 1961 August 11 at 09:57:40.3 UTC
Ecliptic Conjunction 1961 August 11 at 10:36:17.9 UTC
Greatest Duration 1961 August 11 at 10:45:02.0 UTC
Greatest Eclipse 1961 August 11 at 10:46:46.9 UTC
Equatorial Conjunction 1961 August 11 at 11:09:44.1 UTC
Last Umbral Internal Contact 1961 August 11 at 11:35:36.6 UTC
Last Central Line 1961 August 11 at 11:41:06.3 UTC
Last Umbral External Contact 1961 August 11 at 11:46:11.6 UTC
Last Penumbral External Contact 1961 August 11 at 13:19:57.6 UTC
August 11, 1961 Solar Eclipse Parameters
Parameter Value
Eclipse Magnitude 0.93753
Eclipse Obscuration 0.87897
Gamma −0.88594
Sun Right Ascension 09h23m48.0s
Sun Declination +15°16'44.3"
Sun Semi-Diameter 15'46.9"
Sun Equatorial Horizontal Parallax 08.7"
Moon Right Ascension 09h23m06.0s
Moon Declination +14°30'09.9"
Moon Semi-Diameter 14'41.9"
Moon Equatorial Horizontal Parallax 0°53'56.8"
ΔT 33.8 s

Eclipse season

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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.

Eclipse season of August 1961
August 11
Ascending node (new moon)
August 26
Descending node (full moon)
Annular solar eclipse
Solar Saros 125
Partial lunar eclipse
Lunar Saros 137
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Eclipses in 1961

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Metonic

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Tzolkinex

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Half-Saros

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Tritos

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Solar Saros 125

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Inex

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Triad

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Solar eclipses of 1961–1964

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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.[4]

The partial solar eclipses on June 10, 1964 and December 4, 1964 occur in the next lunar year eclipse set.

Solar eclipse series sets from 1961 to 1964
Descending node   Ascending node
Saros Map Gamma Saros Map Gamma
120
February 15, 1961

Total
0.883 125 August 11, 1961

Annular
−0.8859
130 February 5, 1962

Total
0.2107 135 July 31, 1962

Annular
−0.113
140 January 25, 1963

Annular
−0.4898 145 July 20, 1963

Total
0.6571
150 January 14, 1964

Partial
−1.2354 155 July 9, 1964

Partial
1.3623

Saros 125

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This eclipse is a part of Saros series 125, repeating every 18 years, 11 days, and containing 73 events. The series started with a partial solar eclipse on February 4, 1060. It contains total eclipses from June 13, 1276 through July 16, 1330; hybrid eclipses on July 26, 1348 and August 7, 1366; and annular eclipses from August 17, 1384 through August 22, 1979. The series ends at member 73 as a partial eclipse on April 9, 2358. 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 longest duration of totality was produced by member 14 at 1 minutes, 11 seconds on June 25, 1294, and the longest duration of annularity was produced by member 48 at 7 minutes, 23 seconds on July 10, 1907. All eclipses in this series occur at the Moon’s ascending node of orbit.[5]

Series members 43–64 occur between 1801 and 2200:
43 44 45

May 16, 1817

May 27, 1835

June 6, 1853
46 47 48

June 18, 1871

June 28, 1889

July 10, 1907
49 50 51

July 20, 1925

August 1, 1943

August 11, 1961
52 53 54

August 22, 1979

September 2, 1997

September 13, 2015
55 56 57

September 23, 2033

October 4, 2051

October 15, 2069
58 59 60

October 26, 2087

November 6, 2105

November 18, 2123
61 62 63

November 28, 2141

December 9, 2159

December 20, 2177
64

December 31, 2195

Metonic series

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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). All eclipses in this table occur at the Moon's ascending node.

22 eclipse events between January 5, 1935 and August 11, 2018
January 4–5 October 23–24 August 10–12 May 30–31 March 18–19
111 113 115 117 119

January 5, 1935

August 12, 1942

May 30, 1946

March 18, 1950
121 123 125 127 129

January 5, 1954

October 23, 1957

August 11, 1961

May 30, 1965

March 18, 1969
131 133 135 137 139

January 4, 1973

October 23, 1976

August 10, 1980

May 30, 1984

March 18, 1988
141 143 145 147 149

January 4, 1992

October 24, 1995

August 11, 1999

May 31, 2003

March 19, 2007
151 153 155

January 4, 2011

October 23, 2014

August 11, 2018

Tritos series

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This eclipse is a part of a tritos cycle, repeating at alternating nodes every 135 synodic months (≈ 3986.63 days, or 11 years minus 1 month). Their appearance and longitude are irregular due to a lack of synchronization with the anomalistic month (period of perigee), but groupings of 3 tritos cycles (≈ 33 years minus 3 months) come close (≈ 434.044 anomalistic months), so eclipses are similar in these groupings.

Series members between 1801 and 2200

October 19, 1808
(Saros 111)

September 19, 1819
(Saros 112)

August 18, 1830
(Saros 113)

July 18, 1841
(Saros 114)

June 17, 1852
(Saros 115)

May 17, 1863
(Saros 116)

April 16, 1874
(Saros 117)

March 16, 1885
(Saros 118)

February 13, 1896
(Saros 119)

January 14, 1907
(Saros 120)

December 14, 1917
(Saros 121)

November 12, 1928
(Saros 122)

October 12, 1939
(Saros 123)

September 12, 1950
(Saros 124)

August 11, 1961
(Saros 125)

July 10, 1972
(Saros 126)

June 11, 1983
(Saros 127)

May 10, 1994
(Saros 128)

April 8, 2005
(Saros 129)

March 9, 2016
(Saros 130)

February 6, 2027
(Saros 131)

January 5, 2038
(Saros 132)

December 5, 2048
(Saros 133)

November 5, 2059
(Saros 134)

October 4, 2070
(Saros 135)

September 3, 2081
(Saros 136)

August 3, 2092
(Saros 137)

July 4, 2103
(Saros 138)

June 3, 2114
(Saros 139)

May 3, 2125
(Saros 140)

April 1, 2136
(Saros 141)

March 2, 2147
(Saros 142)

January 30, 2158
(Saros 143)

December 29, 2168
(Saros 144)

November 28, 2179
(Saros 145)

October 29, 2190
(Saros 146)

Inex series

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This eclipse is a part of the long period inex cycle, repeating at alternating nodes, every 358 synodic months (≈ 10,571.95 days, or 29 years minus 20 days). Their appearance and longitude are irregular due to a lack of synchronization with the anomalistic month (period of perigee). However, groupings of 3 inex cycles (≈ 87 years minus 2 months) comes close (≈ 1,151.02 anomalistic months), so eclipses are similar in these groupings.

Series members between 1801 and 2200

November 19, 1816
(Saros 120)

October 30, 1845
(Saros 121)

October 10, 1874
(Saros 122)

September 21, 1903
(Saros 123)

August 31, 1932
(Saros 124)

August 11, 1961
(Saros 125)

July 22, 1990
(Saros 126)

July 2, 2019
(Saros 127)

June 11, 2048
(Saros 128)

May 22, 2077
(Saros 129)

May 3, 2106
(Saros 130)

April 13, 2135
(Saros 131)

March 23, 2164
(Saros 132)

March 3, 2193
(Saros 133)

Notes

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  1. ^ "August 11, 1961 Annular Solar Eclipse". timeanddate. Retrieved 7 August 2024.
  2. ^ "Moon Distances for London, United Kingdom, England". timeanddate. Retrieved 7 August 2024.
  3. ^ "Annular Solar Eclipse of 1961 Aug 11". EclipseWise.com. Retrieved 7 August 2024.
  4. ^ 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.
  5. ^ "NASA - Catalog of Solar Eclipses of Saros 125". eclipse.gsfc.nasa.gov.

References

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