Solar eclipse of September 7, 1820
PreviousSolar eclipse of March 14, 1820
NextSolar eclipse of March 4, 1821

An annular solar eclipse occurred at the Moon's descending node of orbit on Thursday, September 7, 1820, with a magnitude of 0.9329. 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 only about 5 hours before apogee (on September 7, 1820, at 18:50 UTC), the Moon's apparent diameter was smaller.[1]

The path of annularity was visible from parts of modern-day northern Canada, Greenland, western Norway, Denmark, the Netherlands, Germany, Switzerland, the Czech Republic, Austria, Italy, Slovenia, Croatia, Bosnia and Herzegovina, Montenegro, Albania, Greece, northeastern Libya, Egypt, Israel, Jordan, and Saudi Arabia. A partial solar eclipse was also visible for parts of northern North America, Europe, North Africa, the Middle East, and Central Asia.

Observation and prediction

This map was drawn in the book Elementa eclipsium, published in Prague in 1816, by Franz Ignaz Cassian Hallaschka (František Ignác Kassián Halaška) (1780-1847), contained maps of the paths of solar eclipses from 1816 and 1860. The geometric constructions used by Hallaschka anticipated the standard theory of eclipses later developed by Friedrich Wilhelm Bessel.[2]

Eclipse details

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]

September 7, 1820 Solar Eclipse Times
EventTime (UTC)
First Penumbral External Contact1820 September 7 at 11:21:45.1 UTC
First Umbral External Contact1820 September 7 at 12:48:53.2 UTC
First Central Line1820 September 7 at 12:53:29.4 UTC
First Umbral Internal Contact1820 September 7 at 12:58:19.3 UTC
Equatorial Conjunction1820 September 7 at 13:06:52.6 UTC
Ecliptic Conjunction1820 September 7 at 13:50:09.9 UTC
Greatest Duration1820 September 7 at 13:57:39.4 UTC
Greatest Eclipse1820 September 7 at 13:59:57.6 UTC
Last Umbral Internal Contact1820 September 7 at 15:02:09.4 UTC
Last Central Line1820 September 7 at 15:06:58.7 UTC
Last Umbral External Contact1820 September 7 at 15:11:34.3 UTC
Last Penumbral External Contact1820 September 7 at 16:38:31.5 UTC
September 7, 1820 Solar Eclipse Parameters
ParameterValue
Eclipse Magnitude0.93295
Eclipse Obscuration0.87040
Gamma0.82506
Sun Right Ascension11h04m02.1s
Sun Declination+05°59'29.3"
Sun Semi-Diameter15'53.0"
Sun Equatorial Horizontal Parallax08.7"
Moon Right Ascension11h05m27.2s
Moon Declination+06°38'30.8"
Moon Semi-Diameter14'41.9"
Moon Equatorial Horizontal Parallax0°53'56.6"
ΔT11.4 s

Eclipse season

See also: Eclipse cycle

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 September 1820
September 7
Descending node (new moon)
September 22
Ascending node (full moon)
Annular solar eclipse
Solar Saros 122		Partial lunar eclipse
Lunar Saros 134

Eclipses in 1820

Metonic

Tzolkinex

Half-Saros

Tritos

Solar Saros 122

Inex

Triad

Solar eclipses of 1819–1823

The partial solar eclipses on April 24, 1819 and October 19, 1819 occur in the previous lunar year eclipse set, and the partial solar eclipses on January 12, 1823 and July 8, 1823 occur in the next lunar year eclipse set.

Solar eclipse series sets from 1819 to 1823
Ascending node Descending node
SarosMapGammaSarosMapGamma
107March 25, 1819

Partial		−1.4722112September 19, 1819

Partial		1.5258
117March 14, 1820

Total		−0.7199122September 7, 1820

Annular		0.8251
127March 4, 1821

Total		−0.0284132August 27, 1821

Annular		0.0671
137February 21, 1822

Annular		0.6914142August 16, 1822

Total		−0.6904
147February 11, 1823

Partial		−1.5413152August 6, 1823

Partial		1.4546

Metonic series

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

22 eclipse events between September 8, 1801 and September 7, 1877
September 7–8June 26–27April 14–15January 31–February 1November 19–20
112114116118120

September 8, 1801
June 26, 1805
April 14, 1809
February 1, 1813
November 19, 1816
122124126128130

September 7, 1820
June 26, 1824
April 14, 1828
February 1, 1832
November 20, 1835
132134136138140

September 7, 1839
June 27, 1843
April 15, 1847
February 1, 1851
November 20, 1854
142144146148150

September 7, 1858
June 27, 1862
April 15, 1866
January 31, 1870
November 20, 1873
152

September 7, 1877

Notes

  1. ^ "Moon Distances for London, United Kingdom, England". timeanddate. Retrieved 22 September 2024.
  2. ^ Historical eclipses in Europe
  3. ^ "Annular Solar Eclipse of 1820 Sep 07". EclipseWise.com. Retrieved 22 September 2024.

References