| Total eclipse | |||||||||||||||||
 The Moon's hourly motion shown right to left | |||||||||||||||||
| Date | February 10, 1971 | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Gamma | 0.2741 | ||||||||||||||||
| Magnitude | 1.3082 | ||||||||||||||||
| Saros cycle | 123 (50 of 73) | ||||||||||||||||
| Totality | 82 minutes, 11 seconds | ||||||||||||||||
| Partiality | 224 minutes, 41 seconds | ||||||||||||||||
| Penumbral | 369 minutes, 31 seconds | ||||||||||||||||
| |||||||||||||||||
A totallunar eclipse occurred at the Moon’sdescending node of orbit on Wednesday, February 10, 1971,[1] with an umbralmagnitude of 1.3082. A lunar eclipse occurs when theMoon moves into theEarth's shadow, causing the Moon to be darkened. A total lunar eclipse occurs when the Moon's near side entirely passes into the Earth's umbral shadow. Unlike asolar eclipse, which can only be viewed from a relatively small area of the world, a lunar eclipse may be viewed from anywhere on thenight side of Earth. A total lunar eclipse can last up to nearly two hours, while a total solar eclipse lasts only a few minutes at any given place, because the Moon'sshadow is smaller. Occurring about 2.8 days beforeapogee (on February 13, 1971, at 2:10 UTC), the Moon's apparent diameter was smaller.[2]
The eclipse was completely visible overNorth America and northwesternSouth America, seen rising overeast Asia andnortheast Asia andAustralia and setting over much of South America,Europe, andwest andcentral Africa.[3]
 |
Shown below is a table displaying details about this particular solar eclipse. It describes various parameters pertaining to this eclipse.[4]
| Parameter | Value |
|---|---|
| Penumbral Magnitude | 2.40262 |
| Umbral Magnitude | 1.30819 |
| Gamma | 0.27413 |
| Sun Right Ascension | 21h33m15.2s |
| Sun Declination | -14°31'31.4" |
| Sun Semi-Diameter | 16'12.5" |
| Sun Equatorial Horizontal Parallax | 08.9" |
| Moon Right Ascension | 09h33m40.7s |
| Moon Declination | +14°45'05.5" |
| Moon Semi-Diameter | 14'48.6" |
| Moon Equatorial Horizontal Parallax | 0°54'21.2" |
| ΔT | 41.3 s |
This eclipse is part of aneclipse 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 afortnight.
| February 10 Descending node (full moon) | February 25 Ascending node (new moon) |
|---|---|
|  |
| Total lunar eclipse Lunar Saros 123 | Partial solar eclipse Solar Saros 149 |
This eclipse is a member of asemester series. An eclipse in a semester series of lunar eclipses repeats approximately every 177 days and 4 hours (a semester) at alternatingnodes of the Moon's orbit.[5]
The penumbral lunar eclipses onApril 2, 1969 andSeptember 25, 1969 occur in the previous lunar year eclipse set, and the lunar eclipses onJune 15, 1973 (penumbral) andDecember 10, 1973 (partial) occur in the next lunar year eclipse set.
| Lunar eclipse series sets from 1969 to 1973 | ||||||||
|---|---|---|---|---|---|---|---|---|
| Ascending node | Descending node | |||||||
| Saros | Date Viewing | Type Chart | Gamma | Saros | Date Viewing | Type Chart | Gamma | |
| 108 | 1969 Aug 27 | Penumbral | −1.5407 | 113 | 1970 Feb 21 | Partial | 0.9620 | |
| 118 | 1970 Aug 17 | Partial | −0.8053 | 123 | 1971 Feb 10 | Total | 0.2741 | |
| 128 | 1971 Aug 06 | Total | −0.0794 | 133 | 1972 Jan 30 | Total | −0.4273 | |
| 138 | 1972 Jul 26 | Partial | 0.7117 | 143 | 1973 Jan 18 | Penumbral | −1.0845 | |
| 148 | 1973 Jul 15 | Penumbral | 1.5178 | |||||
This eclipse is a part ofSaros series 123, repeating every 18 years, 11 days, and containing 72 events. The series started with a penumbral lunar eclipse on August 16, 1087. It contains partial eclipses from May 2, 1520 through July 6, 1610; total eclipses from July 16, 1628 throughApril 4, 2061; and a second set of partial eclipses fromApril 16, 2079 through July 2, 2205. The series ends at member 72 as a penumbral eclipse on October 8, 2367.
The longest duration of totality was produced by member 37 at 105 minutes, 58 seconds on September 20, 1736. All eclipses in this series occur at the Moon’sdescending node of orbit.[6]
| Greatest | First | |||
|---|---|---|---|---|
| The greatest eclipse of the series occurred on1736 Sep 20, lasting 105 minutes, 58 seconds.[7] | Penumbral | Partial | Total | Central |
| 1087 Aug 16 | 1520 May 02 | 1628 Jul 16 | 1682 Aug 18 | |
| Last | ||||
| Central | Total | Partial | Penumbral | |
1953 Jan 29 | 2061 Apr 04 | 2205 Jul 02 | 2367 Oct 08 | |
Eclipses are tabulated in three columns; every third eclipse in the same column is oneexeligmos apart, so they all cast shadows over approximately the same parts of the Earth.
| Series members 41–62 occur between 1801 and 2200: | |||||
|---|---|---|---|---|---|
| 41 | 42 | 43 | |||
| 1808 Nov 03 | 1826 Nov 14 | 1844 Nov 24 | |||
| 44 | 45 | 46 | |||
| 1862 Dec 06 | 1880 Dec 16 | 1898 Dec 27 | |||
| 47 | 48 | 49 | |||
| 1917 Jan 08 | 1935 Jan 19 | 1953 Jan 29 | |||
 |  |  |  | |  |
| 50 | 51 | 52 | |||
| 1971 Feb 10 | 1989 Feb 20 | 2007 Mar 03 | |||
| |  |  |  |  |
| 53 | 54 | 55 | |||
| 2025 Mar 14 | 2043 Mar 25 | 2061 Apr 04 | |||
 |  |  |  | ||
| 56 | 57 | 58 | |||
| 2079 Apr 16 | 2097 Apr 26 | 2115 May 08 | |||
| 59 | 60 | 61 | |||
| 2133 May 19 | 2151 May 30 | 2169 Jun 09 | |||
| 62 | |||||
| 2187 Jun 20 | |||||
This eclipse is a part of atritos cycle, repeating at alternating nodes every 135synodic months (≈ 3986.63 days, or 11 years minus 1 month). Their appearance and longitude are irregular due to a lack of synchronization with theanomalistic 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 1801 and 2200 | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| 1807 May 21 (Saros 108) | 1818 Apr 21 (Saros 109) | 1829 Mar 20 (Saros 110) | 1840 Feb 17 (Saros 111) | 1851 Jan 17 (Saros 112) | |||||
| 1861 Dec 17 (Saros 113) | 1872 Nov 15 (Saros 114) | 1883 Oct 16 (Saros 115) | 1894 Sep 15 (Saros 116) | 1905 Aug 15 (Saros 117) | |||||
 |  | ||||||||
| 1916 Jul 15 (Saros 118) | 1927 Jun 15 (Saros 119) | 1938 May 14 (Saros 120) | 1949 Apr 13 (Saros 121) | 1960 Mar 13 (Saros 122) | |||||
 |  |  |  |  |  |  |  |  |  |
| 1971 Feb 10 (Saros 123) | 1982 Jan 09 (Saros 124) | 1992 Dec 09 (Saros 125) | 2003 Nov 09 (Saros 126) | 2014 Oct 08 (Saros 127) | |||||
| |  |  |  |  |  |  |  |  |
| 2025 Sep 07 (Saros 128) | 2036 Aug 07 (Saros 129) | 2047 Jul 07 (Saros 130) | 2058 Jun 06 (Saros 131) | 2069 May 06 (Saros 132) | |||||
 |  |  |  |  |  |  |  |  |  |
| 2080 Apr 04 (Saros 133) | 2091 Mar 05 (Saros 134) | 2102 Feb 03 (Saros 135) | 2113 Jan 02 (Saros 136) | 2123 Dec 03 (Saros 137) | |||||
 |  |  |  | ||||||
| 2134 Nov 02 (Saros 138) | 2145 Sep 30 (Saros 139) | 2156 Aug 30 (Saros 140) | 2167 Aug 01 (Saros 141) | 2178 Jun 30 (Saros 142) | |||||
| 2189 May 29 (Saros 143) | 2200 Apr 30 (Saros 144) | ||||||||
This eclipse is a part of the long periodinex cycle, repeating at alternating nodes, every 358synodic months (≈ 10,571.95 days, or 29 years minus 20 days). Their appearance and longitude are irregular due to a lack of synchronization with theanomalistic 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 | |||||
|---|---|---|---|---|---|
| 1826 May 21 (Saros 118) | 1855 May 02 (Saros 119) | 1884 Apr 10 (Saros 120) | |||
| 1913 Mar 22 (Saros 121) | 1942 Mar 03 (Saros 122) | 1971 Feb 10 (Saros 123) | |||
 |  |  |  | | |
| 2000 Jan 21 (Saros 124) | 2028 Dec 31 (Saros 125) | 2057 Dec 11 (Saros 126) | |||
 |  |  |  |  |  |
| 2086 Nov 20 (Saros 127) | 2115 Nov 02 (Saros 128) | 2144 Oct 11 (Saros 129) | |||
| 2173 Sep 21 (Saros 130) | |||||
A lunar eclipse will be preceded and followed by solar eclipses by 9 years and 5.5 days (ahalf saros).[8] This lunar eclipse is related to two total solar eclipses ofSolar Saros 130.
| February 5, 1962 | February 16, 1980 |
|---|---|
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