A penumbral lunar eclipse occurred at the Moon’s descending node of orbit on Wednesday, May 4, 1966, with an umbral magnitude of −0.0727. A lunar eclipse occurs when the Moon moves into the Earth's shadow, causing the Moon to be darkened. A penumbral lunar eclipse occurs when part or all of the Moon's near side passes into the Earth's penumbra. Unlike a solar eclipse, which can only be viewed from a relatively small area of the world, a lunar eclipse may be viewed from anywhere on the night side of Earth. Occurring about 2.75 days after perigee (on May 1, 1966, at 15:20 UTC), the Moon's apparent diameter was larger.

Visibility

The eclipse was completely visible over Africa, Europe, the western half of Asia, and Antarctica, seen rising over South America and the Atlantic Ocean and setting over east Asia and Australia.

Eclipse details

Shown below is a table displaying details about this particular lunar eclipse. It describes various parameters pertaining to this eclipse.

May 4, 1966 Lunar Eclipse Parameters
ParameterValue
Penumbral Magnitude0.91576
Umbral Magnitude−0.07272
Gamma1.05536
Sun Right Ascension02h45m54.8s
Sun Declination+16°01'34.2"
Sun Semi-Diameter15'51.5"
Sun Equatorial Horizontal Parallax08.7"
Moon Right Ascension14h47m34.9s
Moon Declination-15°04'18.1"
Moon Semi-Diameter16'02.6"
Moon Equatorial Horizontal Parallax0°58'52.9"
ΔT36.8 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 1966
May 4 Descending node (full moon)May 20 Ascending node (new moon)
Penumbral lunar eclipse Lunar Saros 111Annular solar eclipse Solar Saros 137

Related eclipses

Eclipses in 1966

Metonic

Tzolkinex

Half-Saros

Tritos

Lunar Saros 111

Inex

Triad

Lunar eclipses of 1966–1969

This eclipse is a member of a semester series. An eclipse in a semester series of lunar eclipses repeats approximately every 177 days and 4 hours (a semester) at alternating nodes of the Moon's orbit.

The penumbral lunar eclipse on August 27, 1969 occurs in the next lunar year eclipse set.

Lunar eclipse series sets from 1966 to 1969
Descending nodeAscending node
SarosDate ViewingType ChartGammaSarosDate ViewingType ChartGamma
1111966 May 04Penumbral1.05541161966 Oct 29Penumbral−1.0600
1211967 Apr 24Total0.29721261967 Oct 18Total−0.3653
1311968 Apr 13Total−0.41731361968 Oct 06Total0.3605
1411969 Apr 02Penumbral−1.17651461969 Sep 25Penumbral1.0656

Metonic series

The metonic cycle repeats nearly exactly every 19 years and represents a Saros cycle plus one lunar year. Because it occurs on the same calendar date, the Earth's shadow will in nearly the same location relative to the background stars.

Metonic events: May 4 and October 28
Descending nodeAscending node
1966 May 4 - Penumbral (111) 1985 May 4 - Total (121) 2004 May 4 - Total (131) 2023 May 5 - Penumbral (141)1966 Oct 29 - Penumbral (116) 1985 Oct 28 - Total (126) 2004 Oct 28 - Total (136) 2023 Oct 28 - Partial (146) 2042 Oct 28 - Penumbral (156)

Saros 111

This eclipse is a part of Saros series 111, repeating every 18 years, 11 days, and containing 71 events. The series started with a penumbral lunar eclipse on June 10, 830 AD. It contains partial eclipses from September 14, 992 AD through April 8, 1335; total eclipses from April 19, 1353 through August 4, 1533; and a second set of partial eclipses from August 16, 1551 through April 23, 1948. The series ends at member 71 as a penumbral eclipse on July 19, 2092.

The longest duration of totality was produced by member 35 at 106 minutes, 14 seconds on June 12, 1443. All eclipses in this series occur at the Moon’s descending node of orbit.

GreatestFirst
The greatest eclipse of the series occurred on 1443 Jun 12, lasting 106 minutes, 14 seconds.PenumbralPartialTotalCentral
830 Jun 10992 Sep 141353 Apr 191389 May 10
Last
CentralTotalPartialPenumbral
1497 Jul 141533 Aug 041948 Apr 232092 Jul 19

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.

Series members 55–71 occur between 1801 and 2092:
555657
1804 Jan 261822 Feb 061840 Feb 17
585960
1858 Feb 271876 Mar 101894 Mar 21
616263
1912 Apr 011930 Apr 131948 Apr 23
646566
1966 May 041984 May 152002 May 26
676869
2020 Jun 052038 Jun 172056 Jun 27
7071
2074 Jul 082092 Jul 19

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 1835 and 2200
1835 May 12 (Saros 99)1846 Apr 11 (Saros 100)1868 Feb 08 (Saros 102)1879 Jan 08 (Saros 103)
1933 Aug 05 (Saros 108)
1944 Jul 06 (Saros 109)1955 Jun 05 (Saros 110)1966 May 04 (Saros 111)1977 Apr 04 (Saros 112)1988 Mar 03 (Saros 113)
1999 Jan 31 (Saros 114)2009 Dec 31 (Saros 115)2020 Nov 30 (Saros 116)2031 Oct 30 (Saros 117)2042 Sep 29 (Saros 118)
2053 Aug 29 (Saros 119)2064 Jul 28 (Saros 120)2075 Jun 28 (Saros 121)2086 May 28 (Saros 122)2097 Apr 26 (Saros 123)
2108 Mar 27 (Saros 124)2119 Feb 25 (Saros 125)2130 Jan 24 (Saros 126)2140 Dec 23 (Saros 127)2151 Nov 24 (Saros 128)
2162 Oct 23 (Saros 129)2173 Sep 21 (Saros 130)2184 Aug 21 (Saros 131)2195 Jul 22 (Saros 132)

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
1821 Aug 13 (Saros 106)1850 Jul 24 (Saros 107)1879 Jul 03 (Saros 108)
1908 Jun 14 (Saros 109)1937 May 25 (Saros 110)1966 May 04 (Saros 111)
1995 Apr 15 (Saros 112)2024 Mar 25 (Saros 113)2053 Mar 04 (Saros 114)
2082 Feb 13 (Saros 115)2111 Jan 25 (Saros 116)2140 Jan 04 (Saros 117)
2168 Dec 14 (Saros 118)2197 Nov 24 (Saros 119)

Half-Saros cycle

A lunar eclipse will be preceded and followed by solar eclipses by 9 years and 5.5 days (a half saros). This lunar eclipse is related to two solar eclipses of Solar Saros 118.

April 30, 1957May 11, 1975

See also

Notes

External links