# Solar eclipse of May 11, 1975

A partial solar eclipse occurred at the Moon's descending node of orbit on Sunday, May 11, 1975, with a magnitude of 0.8636. 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 partial solar eclipse occurs in the polar regions of the Earth when the center of the Moon's shadow misses the Earth.
A partial eclipse was visible for parts of North Africa, Europe, North Asia, Greenland, and northern Canada.

## 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.
May 11, 1975 Solar Eclipse Times :
| Event | Time (UTC) |
| First Penumbral External Contact | 1975 May 11 at 05:09:12.6 UTC |
| Ecliptic Conjunction | 1975 May 11 at 07:05:38.4 UTC |
| Greatest Eclipse | 1975 May 11 at 07:17:33.1 UTC |
| Equatorial Conjunction | 1975 May 11 at 07:38:39.4 UTC |
| Last Penumbral External Contact | 1975 May 11 at 09:25:38.4 UTC |
May 11, 1975 Solar Eclipse Parameters :
| Parameter | Value |
| Eclipse Magnitude | 0.86361 |
| Eclipse Obscuration | 0.81627 |
| Gamma | 1.06472 |
| Sun Right Ascension | 03h10m11.2s |
| Sun Declination | +17°44'25.7" |
| Sun Semi-Diameter | 15'50.1" |
| Sun Equatorial Horizontal Parallax | 08.7" |
| Moon Right Ascension | 03h09m27.7s |
| Moon Declination | +18°43'13.9" |
| Moon Semi-Diameter | 15'19.1" |
| Moon Equatorial Horizontal Parallax | 0°56'13.2" |
| ΔT | 45.8 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 May 1975 :
| May 11 Descending node (new moon) | May 25 Ascending node (full moon) |
| Partial solar eclipse Solar Saros 118 | Total lunar eclipse Lunar Saros 130 |

## Related eclipses
### Eclipses in 1975

* A partial solar eclipse on May 11.
* A total lunar eclipse on May 25.
* A partial solar eclipse on November 3.
* A total lunar eclipse on November 18.

### Metonic

* Preceded by: Solar eclipse of July 22, 1971
* Followed by: Solar eclipse of February 26, 1979

### Tzolkinex

* Preceded by: Solar eclipse of March 28, 1968
* Followed by: Solar eclipse of June 21, 1982

### Half-Saros

* Preceded by: Lunar eclipse of May 4, 1966
* Followed by: Lunar eclipse of May 15, 1984

### Tritos

* Preceded by: Solar eclipse of June 10, 1964
* Followed by: Solar eclipse of April 9, 1986

### Solar Saros 118

* Preceded by: Solar eclipse of April 30, 1957
* Followed by: Solar eclipse of May 21, 1993

### Inex

* Preceded by: Solar eclipse of May 30, 1946
* Followed by: Solar eclipse of April 19, 2004

### Triad

* Preceded by: Solar eclipse of July 9, 1888
* Followed by: Solar eclipse of March 11, 2062

### Solar eclipses of 1975–1978

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.
Solar eclipse series sets from 1975 to 1978 :
| Descending node | Descending node | Descending node | Ascending node | Ascending node | Ascending node |
| Saros | Map | Gamma | Saros | Map | Gamma |
| 118 | May 11, 1975 Partial | 1.0647 | 123 | November 3, 1975 Partial | −1.0248 |
| 128 | April 29, 1976 Annular | 0.3378 | 133 | October 23, 1976 Total | −0.327 |
| 138 | April 18, 1977 Annular | −0.399 | 143 | October 12, 1977 Total | 0.3836 |
| 148 | April 7, 1978 Partial | −1.1081 | 153 | October 2, 1978 Partial | 1.1616 |

### Saros 118

This eclipse is a part of Saros series 118, repeating every 18 years, 11 days, and containing 72 events. The series started with a partial solar eclipse on May 24, 803 AD. It contains total eclipses from August 19, 947 AD through October 25, 1650; hybrid eclipses on November 4, 1668 and November 15, 1686; and annular eclipses from November 27, 1704 through April 30, 1957. The series ends at member 72 as a partial eclipse on July 15, 2083. 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 34 at 6 minutes, 59 seconds on May 16, 1398, and the longest duration of annularity was produced by member 59 at 1 minutes, 58 seconds on February 23, 1849. All eclipses in this series occur at the Moon’s descending node of orbit.
Series members 57–72 occur between 1801 and 2083: :
| 57 | 58 | 59 |
| February 1, 1813 | February 12, 1831 | February 23, 1849 |
| 60 | 61 | 62 |
| March 6, 1867 | March 16, 1885 | March 29, 1903 |
| 63 | 64 | 65 |
| April 8, 1921 | April 19, 1939 | April 30, 1957 |
| 66 | 67 | 68 |
| May 11, 1975 | May 21, 1993 | June 1, 2011 |
| 69 | 70 | 71 |
| June 12, 2029 | June 23, 2047 | July 3, 2065 |
| 72 |
| July 15, 2083 |

### Metonic series

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 descending node.
21 eclipse events between July 22, 1971 and July 22, 2047 :
| July 22 | May 9–11 | February 26–27 | December 14–15 | October 2–3 |
| 116 | 118 | 120 | 122 | 124 |
| July 22, 1971 | May 11, 1975 | February 26, 1979 | December 15, 1982 | October 3, 1986 |
| 126 | 128 | 130 | 132 | 134 |
| July 22, 1990 | May 10, 1994 | February 26, 1998 | December 14, 2001 | October 3, 2005 |
| 136 | 138 | 140 | 142 | 144 |
| July 22, 2009 | May 10, 2013 | February 26, 2017 | December 14, 2020 | October 2, 2024 |
| 146 | 148 | 150 | 152 | 154 |
| July 22, 2028 | May 9, 2032 | February 27, 2036 | December 15, 2039 | October 3, 2043 |
| 156 |
| July 22, 2047 |

### Tritos series

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 1866 and 2200 :
| March 16, 1866 (Saros 108) | | | December 13, 1898 (Saros 111) | |
| | September 12, 1931 (Saros 114) | August 12, 1942 (Saros 115) | July 11, 1953 (Saros 116) | June 10, 1964 (Saros 117) |
| May 11, 1975 (Saros 118) | April 9, 1986 (Saros 119) | March 9, 1997 (Saros 120) | February 7, 2008 (Saros 121) | January 6, 2019 (Saros 122) |
| December 5, 2029 (Saros 123) | November 4, 2040 (Saros 124) | October 4, 2051 (Saros 125) | September 3, 2062 (Saros 126) | August 3, 2073 (Saros 127) |
| July 3, 2084 (Saros 128) | June 2, 2095 (Saros 129) | May 3, 2106 (Saros 130) | April 2, 2117 (Saros 131) | March 1, 2128 (Saros 132) |
| January 30, 2139 (Saros 133) | December 30, 2149 (Saros 134) | November 27, 2160 (Saros 135) | October 29, 2171 (Saros 136) | September 27, 2182 (Saros 137) |
| August 26, 2193 (Saros 138) |

### Inex series

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 8, 1801 (Saros 112) | August 18, 1830 (Saros 113) | July 29, 1859 (Saros 114) |
| July 9, 1888 (Saros 115) | June 19, 1917 (Saros 116) | May 30, 1946 (Saros 117) |
| May 11, 1975 (Saros 118) | April 19, 2004 (Saros 119) | March 30, 2033 (Saros 120) |
| March 11, 2062 (Saros 121) | February 18, 2091 (Saros 122) | January 30, 2120 (Saros 123) |
| January 9, 2149 (Saros 124) | December 20, 2177 (Saros 125) | |