Solar eclipse of March 18, 1969

An annular solar eclipse occurred at the Moon's ascending node of orbit on Tuesday, March 18, 1969,[1] with a magnitude of 0.9954. 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. The Moon's apparent diameter was near the average diameter because it occurred 5.1 days after perigee (on March 13, 1969, at 2:50 UTC) and 7.7 days before apogee (on March 25, 1969, at 19:30 UTC).[2]

Solar eclipse of March 18, 1969
Map
Type of eclipse
NatureAnnular
Gamma−0.2704
Magnitude0.9954
Maximum eclipse
Duration26 s (0 min 26 s)
Coordinates14°48′S 116°18′E / 14.8°S 116.3°E / -14.8; 116.3
Max. width of band16 km (9.9 mi)
Times (UTC)
Greatest eclipse4:54:57
References
Saros129 (49 of 80)
Catalog # (SE5000)9440

Annularity was visible from part of Indonesia, and two atolls (Faraulep and Gaferut) in the Trust Territory of the Pacific Islands which belongs to the Federated States of Micronesia now. A partial eclipse was visible for parts of Madagascar, Antarctica, Australia, Southeast Asia, East Asia, and northern Oceania.

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]

March 18, 1969 Solar Eclipse Times
Event Time (UTC)
First Penumbral External Contact 1969 March 18 at 02:07:06.0 UTC
First Umbral External Contact 1969 March 18 at 03:08:38.9 UTC
First Central Line 1969 March 18 at 03:09:16.7 UTC
Greatest Duration 1969 March 18 at 03:09:16.7 UTC
First Umbral Internal Contact 1969 March 18 at 03:09:54.5 UTC
First Penumbral Internal Contact 1969 March 18 at 04:16:02.5 UTC
Equatorial Conjunction 1969 March 18 at 04:38:24.3 UTC
Ecliptic Conjunction 1969 March 18 at 04:51:59.7 UTC
Greatest Eclipse 1969 March 18 at 04:54:57.2 UTC
Last Penumbral Internal Contact 1969 March 18 at 05:34:13.5 UTC
Last Umbral Internal Contact 1969 March 18 at 06:40:08.1 UTC
Last Central Line 1969 March 18 at 06:40:48.6 UTC
Last Umbral External Contact 1969 March 18 at 06:41:29.2 UTC
Last Penumbral External Contact 1969 March 18 at 07:43:01.1 UTC
March 18, 1969 Solar Eclipse Parameters
Parameter Value
Eclipse Magnitude 0.99545
Eclipse Obscuration 0.99092
Gamma −0.27037
Sun Right Ascension 23h50m32.4s
Sun Declination -01°01'31.8"
Sun Semi-Diameter 16'04.0"
Sun Equatorial Horizontal Parallax 08.8"
Moon Right Ascension 23h51m02.7s
Moon Declination -01°15'08.8"
Moon Semi-Diameter 15'44.8"
Moon Equatorial Horizontal Parallax 0°57'47.6"
ΔT 39.4 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 March–April 1969
March 18
Ascending node (new moon)
April 2
Descending node (full moon)
   
Annular solar eclipse
Solar Saros 129
Penumbral lunar eclipse
Lunar Saros 141
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Eclipses in 1969

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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 129

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Inex

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Triad

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Solar eclipses of 1968–1971

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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 eclipse on July 22, 1971 occurs in the next lunar year eclipse set.

Solar eclipse series sets from 1968 to 1971
Ascending node   Descending node
Saros Map Gamma Saros Map Gamma
119 March 28, 2968
 
Partial
−1.037 124 September 22, 1968
 
Total
0.9451
129 March 18, 1969
 
Annular
−0.2704 134 September 11, 1969
 
Annular
0.2201
139
 
Totality in Williamston, NC
USA
March 7, 1970
 
Total
0.4473 144 August 31, 1970
 
Annular
−0.5364
149 February 25, 1971
 
Partial
1.1188 154 August 20, 1971
 
Partial
−1.2659

Saros 129

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This eclipse is a part of Saros series 129, repeating every 18 years, 11 days, and containing 80 events. The series started with a partial solar eclipse on October 3, 1103. It contains annular eclipses from May 6, 1464 through March 18, 1969; hybrid eclipses from March 29, 1987 through April 20, 2023; and total eclipses from April 30, 2041 through July 26, 2185. The series ends at member 80 as a partial eclipse on February 21, 2528. 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 annularity was produced by member 34 at 5 minutes, 10 seconds on October 4, 1698, and the longest duration of totality will be produced by member 58 at 3 minutes, 43 seconds on June 25, 2131. All eclipses in this series occur at the Moon’s ascending node of orbit.[5]

Series members 40–61 occur between 1801 and 2200:
40 41 42
 
December 10, 1806
 
December 20, 1824
 
December 31, 1842
43 44 45
 
January 11, 1861
 
January 22, 1879
 
February 1, 1897
46 47 48
 
February 14, 1915
 
February 24, 1933
 
March 7, 1951
49 50 51
 
March 18, 1969
 
March 29, 1987
 
April 8, 2005
52 53 54
 
April 20, 2023
 
April 30, 2041
 
May 11, 2059
55 56 57
 
May 22, 2077
 
June 2, 2095
 
June 13, 2113
58 59 60
 
June 25, 2131
 
July 5, 2149
 
July 16, 2167
61
 
July 26, 2185

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
 
June 26, 1805
(Saros 114)
 
May 27, 1816
(Saros 115)
 
April 26, 1827
(Saros 116)
 
March 25, 1838
(Saros 117)
 
February 23, 1849
(Saros 118)
 
January 23, 1860
(Saros 119)
 
December 22, 1870
(Saros 120)
 
November 21, 1881
(Saros 121)
 
October 20, 1892
(Saros 122)
 
September 21, 1903
(Saros 123)
 
August 21, 1914
(Saros 124)
 
July 20, 1925
(Saros 125)
 
June 19, 1936
(Saros 126)
 
May 20, 1947
(Saros 127)
 
April 19, 1958
(Saros 128)
 
March 18, 1969
(Saros 129)
 
February 16, 1980
(Saros 130)
 
January 15, 1991
(Saros 131)
 
December 14, 2001
(Saros 132)
 
November 13, 2012
(Saros 133)
 
October 14, 2023
(Saros 134)
 
September 12, 2034
(Saros 135)
 
August 12, 2045
(Saros 136)
 
July 12, 2056
(Saros 137)
 
June 11, 2067
(Saros 138)
 
May 11, 2078
(Saros 139)
 
April 10, 2089
(Saros 140)
 
March 10, 2100
(Saros 141)
 
February 8, 2111
(Saros 142)
 
January 8, 2122
(Saros 143)
 
December 7, 2132
(Saros 144)
 
November 7, 2143
(Saros 145)
 
October 7, 2154
(Saros 146)
 
September 5, 2165
(Saros 147)
 
August 4, 2176
(Saros 148)
 
July 6, 2187
(Saros 149)
 
June 4, 2198
(Saros 150)

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
 
June 26, 1824
(Saros 124)
 
June 6, 1853
(Saros 125)
 
May 17, 1882
(Saros 126)
 
April 28, 1911
(Saros 127)
 
April 7, 1940
(Saros 128)
 
March 18, 1969
(Saros 129)
 
February 26, 1998
(Saros 130)
 
February 6, 2027
(Saros 131)
 
January 16, 2056
(Saros 132)
 
December 27, 2084
(Saros 133)
 
December 8, 2113
(Saros 134)
 
November 17, 2142
(Saros 135)
 
October 29, 2171
(Saros 136)
 
October 9, 2200
(Saros 137)

Notes

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  1. ^ "March 18, 1969 Annular Solar Eclipse". timeanddate. Retrieved 8 August 2024.
  2. ^ "Moon Distances for London, United Kingdom, England". timeanddate. Retrieved 8 August 2024.
  3. ^ "Annular Solar Eclipse of 1969 Mar 18". EclipseWise.com. Retrieved 8 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 129". eclipse.gsfc.nasa.gov.

References

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