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Solar eclipse of July 22, 1971

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Solar eclipse of July 22, 1971
Map
Type of eclipse
NaturePartial
Gamma1.513
Magnitude0.0689
Maximum eclipse
Coordinates63°30′N 177°00′E / 63.5°N 177°E / 63.5; 177
Times (UTC)
Greatest eclipse9:31:55
References
Saros116 (70 of 70)
Catalog # (SE5000)9446

A partial solar eclipse occurred at the Moon's descending node of orbit on Thursday, July 22, 1971,[1] with a magnitude of 0.0689. 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 partial solar eclipse occurs in the polar regions of the Earth when the center of the Moon's shadow misses the Earth.

A partial eclipse was visible for parts of the eastern Soviet Union and northern Alaska. This was the 70th and final solar eclipse from Solar Saros 116.

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.[2]

July 22, 1971 Solar Eclipse Times
Event Time (UTC)
Equatorial Conjunction 1971 July 22 at 08:38:38.2 UTC
First Penumbral External Contact 1971 July 22 at 08:52:56.7 UTC
Ecliptic Conjunction 1971 July 22 at 09:15:39.4 UTC
Greatest Eclipse 1971 July 22 at 09:31:55.3 UTC
Last Penumbral External Contact 1971 July 22 at 10:11:20.6 UTC
July 22, 1971 Solar Eclipse Parameters
Parameter Value
Eclipse Magnitude 0.06899
Eclipse Obscuration 0.02136
Gamma 1.51298
Sun Right Ascension 08h04m17.6s
Sun Declination +20°22'36.4"
Sun Semi-Diameter 15'44.4"
Sun Equatorial Horizontal Parallax 08.7"
Moon Right Ascension 08h06m05.8s
Moon Declination +21°43'24.7"
Moon Semi-Diameter 15'17.0"
Moon Equatorial Horizontal Parallax 0°56'05.5"
ΔT 41.8 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. The first and last eclipse in this sequence is separated by one synodic month.

Eclipse season of July–August 1971
July 22
Descending node (new moon)
August 6
Ascending node (full moon)
August 20
Descending node (new moon)
Partial solar eclipse
Solar Saros 116
Total lunar eclipse
Lunar Saros 128
Partial solar eclipse
Solar Saros 154
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Eclipses in 1971

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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 116

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Inex

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Triad

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Solar eclipses of 1971–1974

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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.[3]

The partial solar eclipses on February 25, 1971 and August 20, 1971 occur in the previous lunar year eclipse set.

Solar eclipse series sets from 1971 to 1974
Descending node   Ascending node
Saros Map Gamma Saros Map Gamma
116 July 22, 1971

Partial
1.513 121 January 16, 1972

Annular
−0.9365
126 July 10, 1972

Total
0.6872 131 January 4, 1973

Annular
−0.2644
136 June 30, 1973

Total
−0.0785 141 December 24, 1973

Annular
0.4171
146 June 20, 1974

Total
−0.8239 151 December 13, 1974

Partial
1.0797

Saros 116

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This eclipse is a part of Saros series 116, repeating every 18 years, 11 days, and containing 70 events. The series started with a partial solar eclipse on June 23, 727 AD. It contains annular eclipses from October 10, 907 AD through May 6, 1845. There are no hybrid or total eclipses in this set. The series ends at member 70 as a partial eclipse on July 22, 1971. 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 51 at 12 minutes, 2 seconds on December 25, 1628. All eclipses in this series occur at the Moon’s descending node of orbit.[4]

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 descending node.

21 eclipse events between July 22, 1971 and July 22, 2047
July 22 May 9–11 February 26–27 December 14–15 October 2–3
116 118 120 122 124

July 22, 1971

May 11, 1975

February 26, 1979

December 15, 1982

October 3, 1986
126 128 130 132 134

July 22, 1990

May 10, 1994

February 26, 1998

December 14, 2001

October 3, 2005
136 138 140 142 144

July 22, 2009

May 10, 2013

February 26, 2017

December 14, 2020

October 2, 2024
146 148 150 152 154

July 22, 2028

May 9, 2032

February 27, 2036

December 15, 2039

October 3, 2043
156

July 22, 2047

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.

The partial solar eclipses on March 27, 1884 (part of Saros 108) and December 24, 1916 (part of Saros 111) are also a part of this series but are not included in the table below.

Series members between 1971 and 2200

July 22, 1971
(Saros 116)

June 21, 1982
(Saros 117)

May 21, 1993
(Saros 118)

April 19, 2004
(Saros 119)

March 20, 2015
(Saros 120)

February 17, 2026
(Saros 121)

January 16, 2037
(Saros 122)

December 16, 2047
(Saros 123)

November 16, 2058
(Saros 124)

October 15, 2069
(Saros 125)

September 13, 2080
(Saros 126)

August 15, 2091
(Saros 127)

July 15, 2102
(Saros 128)

June 13, 2113
(Saros 129)

May 14, 2124
(Saros 130)

April 13, 2135
(Saros 131)

March 12, 2146
(Saros 132)

February 9, 2157
(Saros 133)

January 10, 2168
(Saros 134)

December 9, 2178
(Saros 135)

November 8, 2189
(Saros 136)

October 9, 2200
(Saros 137)

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

October 31, 1826
(Saros 111)

August 31, 1913
(Saros 114)

August 12, 1942
(Saros 115)

July 22, 1971
(Saros 116)

July 1, 2000
(Saros 117)

June 12, 2029
(Saros 118)

May 22, 2058
(Saros 119)

May 2, 2087
(Saros 120)

April 13, 2116
(Saros 121)

March 23, 2145
(Saros 122)

March 3, 2174
(Saros 123)

References

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  1. ^ "July 22, 1971 Partial Solar Eclipse". timeanddate. Retrieved 8 August 2024.
  2. ^ "Partial Solar Eclipse of 1971 Jul 22". EclipseWise.com. Retrieved 8 August 2024.
  3. ^ 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.
  4. ^ "NASA - Catalog of Solar Eclipses of Saros 116". eclipse.gsfc.nasa.gov.
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