Jump to content

Solar eclipse of August 7, 1869

From Wikipedia, the free encyclopedia
Solar eclipse of August 7, 1869
Totality photographed by Morton's party in Iowa
Map
Type of eclipse
NatureTotal
Gamma0.696
Magnitude1.0551
Maximum eclipse
Duration228 s (3 min 48 s)
Coordinates59°06′N 133°12′W / 59.1°N 133.2°W / 59.1; -133.2
Max. width of band254 km (158 mi)
Times (UTC)
Greatest eclipse22:01:05
References
Saros143 (15 of 72)
Catalog # (SE5000)9209

A total solar eclipse occurred at the Moon's ascending node of orbit between Saturday, August 7 and Sunday, August 8, 1869, with a magnitude of 1.0551. 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. Occurring about 1.6 days before perigee (on August 9, 1869, at 13:20 UTC), the Moon's apparent diameter was larger.[1]

The path of totality was visible from parts of modern-day eastern Russia, Alaska, western Canada, Montana, North Dakota, South Dakota, Minnesota, Nebraska, Iowa, Missouri, Illinois, Indiana, Kentucky, Tennessee, West Virginia, Virginia, North Carolina, and South Carolina. A partial solar eclipse was also visible for parts of Northeast Asia, North America, Central America, and the Caribbean.

Observations

[edit]
George Davidson

In 1869, astronomer and explorer George Davidson made a scientific trip to the Chilkat Valley of Alaska. He told the Chilkat Indians that he was anxious to observe a total eclipse of the sun that was predicted to occur the following day, August 7. This prediction was considered to have saved Davidson's expedition from an attack.[2]

A photographic expedition was organized by Philadelphia's Henry Morton under the authority of John H. C. Coffin, U.S.N., Superintendent of the American Ephemeris and Nautical Almanac. The expedition observed the eclipse in Iowa at three stations: Burlington, Mount Pleasant, and Ottumwa, under the respective supervisions of Alfred M. Mayer, Henry Morton, and Charles Francis Himes (1838–1918).[3]

Observations were also made by meteorology pioneers Cleveland Abbe and General Albert Myer, in Dakota Territory and Virginia, respectively.[4]

Eclipse details

[edit]

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.[5]

August 7, 1869 Solar Eclipse Times
Event Time (UTC)
First Penumbral External Contact 1869 August 07 at 19:38:08.9 UTC
First Umbral External Contact 1869 August 07 at 20:44:43.8 UTC
First Central Line 1869 August 07 at 20:46:19.1 UTC
First Umbral Internal Contact 1869 August 07 at 20:47:55.4 UTC
Equatorial Conjunction 1869 August 07 at 21:46:10.8 UTC
Greatest Duration 1869 August 07 at 22:00:53.7 UTC
Greatest Eclipse 1869 August 07 at 22:01:04.7 UTC
Ecliptic Conjunction 1869 August 07 at 22:08:11.2 UTC
Last Umbral Internal Contact 1869 August 07 at 23:14:22.8 UTC
Last Central Line 1869 August 07 at 23:16:00.7 UTC
Last Umbral External Contact 1869 August 07 at 23:17:37.6 UTC
Last Penumbral External Contact 1869 August 08 at 00:24:03.9 UTC
August 7, 1869 Solar Eclipse Parameters
Parameter Value
Eclipse Magnitude 1.05514
Eclipse Obscuration 1.11332
Gamma 0.69599
Sun Right Ascension 09h11m15.8s
Sun Declination +16°14'37.3"
Sun Semi-Diameter 15'46.6"
Sun Equatorial Horizontal Parallax 08.7"
Moon Right Ascension 09h11m50.9s
Moon Declination +16°55'41.0"
Moon Semi-Diameter 16'27.0"
Moon Equatorial Horizontal Parallax 1°00'22.4"
ΔT 1.2 s

Eclipse season

[edit]

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 July–August 1869
July 23
Descending node (full moon)
August 7
Ascending node (new moon)
Partial lunar eclipse
Lunar Saros 117
Total solar eclipse
Solar Saros 143
[edit]

Eclipses in 1869

[edit]

Metonic

[edit]

Tzolkinex

[edit]

Half-Saros

[edit]

Tritos

[edit]

Solar Saros 143

[edit]

Inex

[edit]

Triad

[edit]

Solar eclipses of 1866–1870

[edit]

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.[6]

The partial solar eclipses on April 15, 1866 and October 8, 1866 occur in the previous lunar year eclipse set, and the solar eclipses on June 28, 1870 (partial) and December 22, 1870 (total) occur in the next lunar year eclipse set.

Solar eclipse series sets from 1866 to 1870
Descending node   Ascending node
Saros Map Gamma Saros Map Gamma
108 March 16, 1866

Partial
1.4241 113
118 March 6, 1867

Annular
0.7716 123 August 29, 1867

Total
−0.7940
128 February 23, 1868

Annular
0.0706 133 August 18, 1868

Total
−0.0443
138 February 11, 1869

Annular
−0.6251 143 August 7, 1869

Total
0.6960
148 January 31, 1870

Partial
−1.2829 153 July 28, 1870

Partial
1.5044

Saros 143

[edit]

This eclipse is a part of Saros series 143, repeating every 18 years, 11 days, and containing 72 events. The series started with a partial solar eclipse on March 7, 1617. It contains total eclipses from June 24, 1797 through October 24, 1995; hybrid eclipses from November 3, 2013 through December 6, 2067; and annular eclipses from December 16, 2085 through September 16, 2536. The series ends at member 72 as a partial eclipse on April 23, 2897. 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 16 at 3 minutes, 50 seconds on August 19, 1887, and the longest duration of annularity will be produced by member 51 at 4 minutes, 54 seconds on September 6, 2518. All eclipses in this series occur at the Moon’s ascending node of orbit.[7]

Series members 12–33 occur between 1801 and 2200:
12 13 14

July 6, 1815

July 17, 1833

July 28, 1851
15 16 17

August 7, 1869

August 19, 1887

August 30, 1905
18 19 20

September 10, 1923

September 21, 1941

October 2, 1959
21 22 23

October 12, 1977

October 24, 1995

November 3, 2013
24 25 26

November 14, 2031

November 25, 2049

December 6, 2067
27 28 29

December 16, 2085

December 29, 2103

January 8, 2122
30 31 32

January 20, 2140

January 30, 2158

February 10, 2176
33

February 21, 2194

Metonic series

[edit]

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.

25 eclipse events between March 14, 1801 and August 7, 1888
March 14–15 December 31–January 1 October 19–20 August 7 May 26–27
107 109 111 113 115

March 14, 1801

January 1, 1805

October 19, 1808

August 7, 1812

May 27, 1816
117 119 121 123 125

March 14, 1820

January 1, 1824

October 20, 1827

August 7, 1831

May 27, 1835
127 129 131 133 135

March 15, 1839

December 31, 1842

October 20, 1846

August 7, 1850

May 26, 1854
137 139 141 143 145

March 15, 1858

December 31, 1861

October 19, 1865

August 7, 1869

May 26, 1873
147 149 151 153

March 15, 1877

December 31, 1880

October 19, 1884

August 7, 1888

Tritos series

[edit]

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 eclipse on October 24, 2098 (part of Saros 164) is also a part of this series but is not included in the table below.

Series members between 1801 and 2011

February 11, 1804
(Saros 137)

January 10, 1815
(Saros 138)

December 9, 1825
(Saros 139)

November 9, 1836
(Saros 140)

October 9, 1847
(Saros 141)

September 7, 1858
(Saros 142)

August 7, 1869
(Saros 143)

July 7, 1880
(Saros 144)

June 6, 1891
(Saros 145)

May 7, 1902
(Saros 146)

April 6, 1913
(Saros 147)

March 5, 1924
(Saros 148)

February 3, 1935
(Saros 149)

January 3, 1946
(Saros 150)

December 2, 1956
(Saros 151)

November 2, 1967
(Saros 152)

October 2, 1978
(Saros 153)

August 31, 1989
(Saros 154)

July 31, 2000
(Saros 155)

July 1, 2011
(Saros 156)

Inex series

[edit]

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

September 17, 1811
(Saros 141)

August 27, 1840
(Saros 142)

August 7, 1869
(Saros 143)

July 18, 1898
(Saros 144)

June 29, 1927
(Saros 145)

June 8, 1956
(Saros 146)

May 19, 1985
(Saros 147)

April 29, 2014
(Saros 148)

April 9, 2043
(Saros 149)

March 19, 2072
(Saros 150)

February 28, 2101
(Saros 151)

February 8, 2130
(Saros 152)

January 19, 2159
(Saros 153)

December 29, 2187
(Saros 154)

Notes

[edit]
  1. ^ "Moon Distances for London, United Kingdom, England". timeanddate. Retrieved 3 September 2024.
  2. ^ August 7, 1869, Astronomer impresses Indians with eclipse George Davidson, a prominent astronomer and explorer, impresses Alaskan Native Americans with his ability to predict a total solar eclipse.
  3. ^ Mayer, Alfred (1869). "An Abstract of Some of the Results of Measurements and Examinations of the Photographs of the Total Solar Eclipse of August 7, 1869". Proceedings of the American Philosophical Society. 11 (81): 204–208.
  4. ^ David Baron, American Eclipse, p. 158
  5. ^ "Total Solar Eclipse of 1869 Aug 07". EclipseWise.com. Retrieved 3 September 2024.
  6. ^ 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.
  7. ^ "NASA - Catalog of Solar Eclipses of Saros 143". eclipse.gsfc.nasa.gov.

References

[edit]