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.
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.Historical eclipses in Europe
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.
+September 7, 1820 Solar Eclipse Times Event Time (UTC) First Penumbral External Contact 1820 September 7 at 11:21:45.1 UTC First Umbral External Contact 1820 September 7 at 12:48:53.2 UTC First Central Line 1820 September 7 at 12:53:29.4 UTC First Umbral Internal Contact 1820 September 7 at 12:58:19.3 UTC Equatorial Conjunction 1820 September 7 at 13:06:52.6 UTC Ecliptic Conjunction 1820 September 7 at 13:50:09.9 UTC Greatest Duration 1820 September 7 at 13:57:39.4 UTC Greatest Eclipse 1820 September 7 at 13:59:57.6 UTC Last Umbral Internal Contact 1820 September 7 at 15:02:09.4 UTC Last Central Line 1820 September 7 at 15:06:58.7 UTC Last Umbral External Contact 1820 September 7 at 15:11:34.3 UTC Last Penumbral External Contact 1820 September 7 at 16:38:31.5 UTC
+September 7, 1820 Solar Eclipse Parameters Parameter Value Eclipse Magnitude 0.93295 Eclipse Obscuration 0.87040 Gamma 0.82506 Sun Right Ascension 11h04m02.1s Sun Declination +05°59'29.3" Sun Semi-Diameter 15'53.0" Sun Equatorial Horizontal Parallax 08.7" Moon Right Ascension 11h05m27.2s Moon Declination +06°38'30.8" Moon Semi-Diameter 14'41.9" Moon Equatorial Horizontal Parallax 0°53'56.6" ΔT 11.4 s
Eclipse season
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 7Descending node (new moon) September 22Ascending node (full moon) Annular solar eclipseSolar Saros 122 Partial lunar eclipseLunar Saros 134
Related eclipses Eclipses in 1820 A total solar eclipse on March 14. A partial lunar eclipse on March 29. An annular solar eclipse on September 7. A partial lunar eclipse on September 22.
Metonic Preceded by: Solar eclipse of November 19, 1816 Followed by: Solar eclipse of June 26, 1824
Tzolkinex Preceded by: Solar eclipse of July 27, 1813 Followed by: Solar eclipse of October 20, 1827
Half-Saros Preceded by: Lunar eclipse of September 2, 1811 Followed by: Lunar eclipse of September 13, 1829
Tritos Preceded by: Solar eclipse of October 9, 1809 Followed by: Solar eclipse of August 7, 1831
Solar Saros 122 Preceded by: Solar eclipse of August 28, 1802 Followed by: Solar eclipse of September 18, 1838
Inex Preceded by: Solar eclipse of September 27, 1791 Followed by: Solar eclipse of August 18, 1849
Triad Preceded by: Solar eclipse of November 6, 1733 Followed by: Solar eclipse of July 10, 1907
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 Saros Map Gamma Saros Map Gamma 107 March 25, 1819Partial −1.4722 112 September 19, 1819Partial 1.5258 117 March 14, 1820Total −0.7199 122 September 7, 1820Annular 0.8251 127 March 4, 1821Total −0.0284 132 August 27, 1821Annular 0.0671 137 February 21, 1822Annular 0.6914 142 August 16, 1822Total −0.6904 147 February 11, 1823Partial −1.5413 152 August 6, 1823Partial 1.4546
Saros 122
Metonic series All eclipses in this table occur at the Moon's descending node.
22 eclipse events between September 8, 1801 and September 7, 1877September 7–8June 26–27April 14–15January 31–February 1November 19–20112114116118120September 8, 1801June 26, 1805April 14, 1809February 1, 1813November 19, 1816122124126128130September 7, 1820June 26, 1824April 14, 1828February 1, 1832November 20, 1835132134136138140September 7, 1839June 27, 1843April 15, 1847February 1, 1851November 20, 1854142144146148150September 7, 1858June 27, 1862April 15, 1866January 31, 1870November 20, 1873152September 7, 1877
Tritos series
Inex series
Notes
References
NASA chart graphics Googlemap NASA Besselian elements
https://adsabs.harvard.edu/full/1822MmRAS...1..217P