A total lunar eclipse occurred at the Moon’s descending node of orbit on Tuesday, July 6, 1982,[1] with an umbral magnitude of 1.7180. It was a central lunar eclipse, in which part of the Moon passed through the center of the Earth's shadow. A lunar eclipse occurs when the Moon moves into the Earth'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 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. 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's shadow is smaller. Occurring about 1.2 days after apogee (on July 5, 1982, at 2:30 UTC), the Moon's apparent diameter was smaller.[2]
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. The first and last eclipse in this sequence is separated by one synodic month.
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.[5]
This eclipse is a part of Saros series 129, repeating every 18 years, 11 days, and containing 71 events. The series started with a penumbral lunar eclipse on June 10, 1351. It contains partial eclipses from September 26, 1531 through May 11, 1892; total eclipses from May 24, 1910 through September 8, 2090; and a second set of partial eclipses from September 20, 2108 through April 26, 2469. The series ends at member 71 as a penumbral eclipse on July 24, 2613.
The longest duration of totality was produced by member 37 at 106 minutes, 24 seconds on July 16, 2000. All eclipses in this series occur at the Moon’s descending node of orbit.[6]
Greatest
First
The greatest eclipse of the series occurred on 2000 Jul 16, lasting 106 minutes, 24 seconds.[7]
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.
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.
The inex series repeats eclipses 20 days short of 29 years, repeating on average every 10571.95 days. This period is equal to 358 lunations (synodic months) and 388.5 draconic months. Saros series increment by one on successive Inex events and repeat at alternate ascending and descending lunar nodes.
This period is 383.6734 anomalistic months (the period of the Moon's elliptical orbital precession). Despite the average 0.05 time-of-day shift between subsequent events, the variation of the Moon in its elliptical orbit at each event causes the actual eclipse time to vary significantly. It is a part of Lunar Inex series 39.
All events in this series listed below and more are total lunar eclipses.
A lunar eclipse will be preceded and followed by solar eclipses by 9 years and 5.5 days (a half saros).[8] This lunar eclipse is related to two total solar eclipses of Solar Saros 136.