A total solar eclipse occurred at the Moon's ascending node of the orbit on July 31, 1981. 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. The continental path of totality fell entirely within the Soviet Union, belonging to Georgia, Kazakhstan and Russia today. The southern part of Mount Elbrus, the highest mountain in Europe, also lies in the path of totality. Occurring only 3.8 days after perigee (Perigee on July 27, 1981), the Moon's apparent diameter was larger. With a path width of 107.8 km (66.984 mi, or 353,674.541 feet), this total solar eclipse had an average path.
| Solar eclipse of July 31, 1981 | |
|---|---|
 Map | |
| Type of eclipse | |
| Nature | Total |
| Gamma | 0.5792 |
| Magnitude | 1.0258 |
| Maximum eclipse | |
| Duration | 122 s (2 min 2 s) |
| Coordinates | 53°18′N 134°06′E / 53.3°N 134.1°E |
| Max. width of band | 108 km (67 mi) |
| Times (UTC) | |
| Greatest eclipse | 3:46:37 |
| References | |
| Saros | 145 (20 of 77) |
| Catalog # (SE5000) | 9467 |
It was the 20th eclipse of the 145th Saros cycle, which began with a partial eclipse on January 4, 1639 and will conclude with a partial eclipse on April 17, 3009.
The moon's apparent diameter was 7 arcseconds larger than the February 4, 1981 annular solar eclipse. [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14]
Related eclipses edit
Eclipses in 1981 edit
- A penumbral lunar eclipse on Tuesday, 20 January 1981.
- An annular solar eclipse on Wednesday, 4 February 1981.
- A partial lunar eclipse on Friday, 17 July 1981.
- A total solar eclipse on Friday, 31 July 1981.
Solar eclipses of 1979–1982 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.[15] There were 8 solar eclipses between February 26, 1979 and July 20, 1982. Were there: February 26, 1979 (total solar eclipse, 0.8 days after perigee, 103.9%, 0.89811 gamma, saros 120), August 22, 1979 (small annular solar eclipse, 0.6 days before apogee, 93.3%, −0.96319 gamma, saros 125), February 16, 1980 (total solar eclipse, 1 day before perigee, 104.3%, 0.22244 gamma, saros 130), August 10, 1980 (large annular solar eclipse, 5 days before apogee, 97.3%, −0.19154 gamma, saros 135), February 4, 1981 (large annular solar eclipse, 4 days before perigee, 99.4%, −0.48375 gamma, saros 140), July 31, 1981 (total solar eclipse, 3.8 days after perigee, 102.6%, 0.57917 gamma, saros 145), January 25, 1982 (moderate partial solar eclipse, 4.7 days after apogee, 56.6%, −1.23110 gamma, saros 150) and July 20, 1982 (small partial solar eclipse, 0.9 days after perigee, 46.4%, 1.28859 gamma, saros 155).
| Solar eclipse series sets from 1979 to 1982 | ||||||
|---|---|---|---|---|---|---|
| Descending node | Ascending node | |||||
| Saros | Map | Gamma | Saros | Map | Gamma | |
| 120 |  1979 February 26 Total |
0.89811 | 125 |  1979 August 22 Annular |
−0.96319 | |
| 130 |  1980 February 16 Total |
0.22244 | 135 |  1980 August 10 Annular |
−0.19154 | |
| 140 |  1981 February 4 Annular |
−0.48375 | 145 | 1981 July 31 Total |
0.57917 | |
| 150 |  1982 January 25 Partial |
−1.23110 | 155 |  1982 July 20 Partial |
1.28859 | |
| Partial solar eclipses on June 21, 1982 and December 15, 1982 occur in the next lunar year eclipse set. | ||||||
Saros 145 edit
This solar eclipse is a part of Saros cycle 145, repeating every 18 years, 11 days, 8 hours, containing 77 events. The series started with a partial solar eclipse on January 4, 1639, and reached a first annular eclipse on June 6, 1891. It was a hybrid event on June 17, 1909, and total eclipses from June 29, 1927, through September 9, 2648. The series ends at member 77 as a partial eclipse on April 17, 3009. The longest eclipse will occur on June 25, 2522, with a maximum duration of totality of 7 minutes, 12 seconds. All eclipses in this series occurs at the Moon's ascending node.
| Series members 10–32 occur between 1801 and 2359 | ||
|---|---|---|
| 10 | 11 | 12 |
 April 13, 1801 |
 April 24, 1819 |
 May 4, 1837 |
| 13 | 14 | 15 |
 May 16, 1855 |
 May 26, 1873 |
 June 6, 1891 |
| 16 | 17 | 18 |
 June 17, 1909 |
 June 29, 1927 |
 July 9, 1945 |
| 19 | 20 | 21 |
 July 20, 1963 |
July 31, 1981 |
 August 11, 1999 |
| 22 | 23 | 24 |
 August 21, 2017 |
 September 2, 2035 |
 September 12, 2053 |
| 25 | 26 | 27 |
 September 23, 2071 |
 October 4, 2089 |
 October 16, 2107 |
| 28 | 29 | 30 |
 October 26, 2125 |
 November 7, 2143 |
 November 17, 2161 |
| 31 | 32 | 33 |
 November 28, 2179 |
 December 9, 2197 |
 December 21, 2215 |
| 34 | 35 | 36 |
 December 31, 2233 |
 January 12, 2252 |
 January 22, 2270 |
| 37 | 38 | 39 |
 February 2, 2288 |
 February 14, 2306 |
 February 25, 2324 |
| 40 | ||
 March 8, 2342 | ||
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.
| Series members between 1901 and 2100 | |||
|---|---|---|---|
 March 6, 1905 (Saros 138) |
 February 3, 1916 (Saros 139) |
 January 3, 1927 (Saros 140) | |
 December 2, 1937 (Saros 141) |
 November 1, 1948 (Saros 142) |
 October 2, 1959 (Saros 143) | |
 August 31, 1970 (Saros 144) |
July 31, 1981 (Saros 145) |
 June 30, 1992 (Saros 146) | |
 May 31, 2003 (Saros 147) |
 April 29, 2014 (Saros 148) |
 March 29, 2025 (Saros 149) | |
 February 27, 2036 (Saros 150) |
 January 26, 2047 (Saros 151) |
 December 26, 2057 (Saros 152) | |
 November 24, 2068 (Saros 153) |
 October 24, 2079 (Saros 154) |
 September 23, 2090 (Saros 155) |
|
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.
| 22 eclipse events between December 24, 1916 and July 31, 2000 | ||||
|---|---|---|---|---|
| December 24–25 | October 12–13 | July 31-Aug 1 | May 18–20 | March 7–8 |
| 91 | 93 | 95 | 97 | 99 |
| December 23, 1878 | October 12, 1882 | July 31, 1886 | May 18, 1890 | March 7, 1894 |
| 101 | 103 | 105 | 107 | 109 |
| December 23, 1897 | October 12, 1901 | August 1, 1905 | May 19, 1909 | March 8, 1913 |
| 111 | 113 | 115 | 117 | 119 |
 December 24, 1916 |
October 12, 1920 |  July 31, 1924 |
 May 19, 1928 |
 March 7, 1932 |
| 121 | 123 | 125 | 127 | 129 |
 December 25, 1935 |
 October 12, 1939 |
 August 1, 1943 |
 May 20, 1947 |
 March 7, 1951 |
| 131 | 133 | 135 | 137 | 139 |
 December 25, 1954 |
 October 12, 1958 |
 July 31, 1962 |
 May 20, 1966 |
 March 7, 1970 |
| 141 | 143 | 145 | 147 | 149 |
 December 24, 1973 |
 October 12, 1977 |
July 31, 1981 |
 May 19, 1985 |
 March 7, 1989 |
| 151 | 153 | 155 | 157 | 159 |
 December 24, 1992 |
 October 12, 1996 |
 July 31, 2000 |
May 19, 2004 | March 7, 2008 |
| 161 | 163 | 165 | 167 | 169 |
| December 24, 2011 | October 13, 2015 | August 1, 2019 | May 19, 2023 | March 8, 2027 |
References edit
- ^ "Muscovites view eclipse of the sun". Spokane Chronicle. Spokane, Washington. 1981-07-31. p. 3. Retrieved 2023-10-18 – via Newspapers.com.
- ^ "Bad weather hampers view of solar eclipse". Abilene Reporter-News. Abilene, Texas. 1981-07-31. p. 16. Retrieved 2023-10-18 – via Newspapers.com.
- ^ "Scientists Get Good Solar Eclipse Look". The Daily Advertiser. Lafayette, Louisiana. 1981-07-31. p. 6. Retrieved 2023-10-18 – via Newspapers.com.
- ^ "Former Beatrician among group studying eclipse in Russia". Beatrice Daily Sun. Beatrice, Nebraska. 1981-07-31. p. 3. Retrieved 2023-10-18 – via Newspapers.com.
- ^ "Clouds obstruct most of Soviet eclipse". Springfield Leader and Press. Springfield, Missouri. 1981-07-31. p. 17. Retrieved 2023-10-18 – via Newspapers.com.
- ^ "High-flying scientists view moon's path across sun". The Kokomo Tribune. Kokomo, Indiana. 1981-07-31. p. 13. Retrieved 2023-10-18 – via Newspapers.com.
- ^ "Long eclipse". Liverpool Echo. Liverpool, Merseyside, England. 1981-07-31. p. 1. Retrieved 2023-10-18 – via Newspapers.com.
- ^ "Black day for Reds". Manchester Evening News. Manchester, Greater Manchester, England. 1981-07-31. p. 1. Retrieved 2023-10-18 – via Newspapers.com.
- ^ "Clouds spoil view of eclipse of sun". Calgary Herald. Calgary, Alberta, Canada. 1981-07-31. p. 14. Retrieved 2023-10-18 – via Newspapers.com.
- ^ "Total eclipse". North Bay Nugget. North Bay, Ontario, Canada. 1981-07-31. p. 2. Retrieved 2023-10-18 – via Newspapers.com.
- ^ "Weather blocks eclipse view". Edmonton Journal. Edmonton, Alberta, Canada. 1981-07-31. p. 48. Retrieved 2023-10-18 – via Newspapers.com.
- ^ "Hundreds of scientists study eclipse of sun". Standard-Speaker. Hazleton, Pennsylvania. 1981-08-01. p. 5. Retrieved 2023-10-18 – via Newspapers.com.
- ^ "Americans Join Scientists to Observe Eclipse". Tulsa World. Tulsa, Oklahoma. 1981-08-01. p. 32. Retrieved 2023-10-18 – via Newspapers.com.
- ^ "Eclipse casts its giant shadow across 4,300-mile Soviet path". Arizona Daily Star. Tucson, Arizona. 1981-08-01. p. 2. Retrieved 2023-10-18 – via Newspapers.com.
- ^ 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.
External links edit
- Earth visibility chart and eclipse statistics Eclipse Predictions by Fred Espenak, NASA/GSFC
- Solar Corona Shape
Photos: