October 1985 lunar eclipse

A total lunar eclipse occurred at the Moon’s ascending node of orbit on Monday, October 28, 1985, with an umbral magnitude of 1.0736. 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 before apogee (on October 29, 1985, at 21:50 UTC), the Moon's apparent diameter was smaller.

This lunar eclipse was the second of a tetrad, with four total lunar eclipses in series, the others being on May 4, 1985; April 24, 1986; and October 17, 1986.

Visibility

The eclipse was completely visible over northern Europe, Asia, and western Australia, seen rising over Africa and much of Europe and setting over eastern Australia, northwestern North America, and the central Pacific Ocean.

Eclipse details

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

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.

Related eclipses

Eclipses in 1985

• A total lunar eclipse on May 4.
• A partial solar eclipse on May 19.
• A total lunar eclipse on October 28.
• A total solar eclipse on November 12.

Metonic

• Preceded by: Lunar eclipse of January 9, 1982
• Followed by: Lunar eclipse of August 17, 1989

Tzolkinex

• Preceded by: Lunar eclipse of September 16, 1978
• Followed by: Lunar eclipse of December 9, 1992

Half-Saros

• Preceded by: Solar eclipse of October 23, 1976
• Followed by: Solar eclipse of November 3, 1994

Tritos

• Preceded by: Lunar eclipse of November 29, 1974
• Followed by: Lunar eclipse of September 27, 1996

Lunar Saros 126

• Preceded by: Lunar eclipse of October 18, 1967
• Followed by: Lunar eclipse of November 9, 2003

Inex

• Preceded by: Lunar eclipse of November 18, 1956
• Followed by: Lunar eclipse of October 8, 2014

Triad

• Preceded by: Lunar eclipse of December 27, 1898
• Followed by: Lunar eclipse of August 28, 2072

Lunar eclipses of 1984–1987

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 June 13, 1984 occurs in the previous lunar year eclipse set.

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.

Saros 126

This eclipse is a part of Saros series 126, repeating every 18 years, 11 days, and containing 70 events. The series started with a penumbral lunar eclipse on July 18, 1228. It contains partial eclipses from March 24, 1625 through June 9, 1751; total eclipses from June 19, 1769 through November 9, 2003; and a second set of partial eclipses from November 19, 2021 through June 5, 2346. The series ends at member 70 as a penumbral eclipse on August 19, 2472.

The longest duration of totality was produced by member 36 at 106 minutes, 27 seconds on August 13, 1859. All eclipses in this series occur at the Moon’s ascending node of orbit.

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.

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.

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.

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 total solar eclipses of Solar Saros 133.

See also

• List of lunar eclipses
• List of 20th-century lunar eclipses

Notes

External links

• Eclipse Predictions by Fred Espenak, NASA/GSFC