September 1998 lunar eclipse
A penumbral lunar eclipse occurred at the Moon’s descending node of orbit on Sunday, September 6, 1998,[1] with an umbral magnitude of −0.1544. 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 1.8 days before perigee (on September 8, 1998, at 7:00 UTC), the Moon's apparent diameter was larger.[2] VisibilityThe eclipse was completely visible over northeast Asia, much of Australia, western North America and the Pacific Ocean, seen rising over east and southeast Asia and western Australia and setting over much of North and South America.[3] Eclipse detailsShown below is a table displaying details about this particular solar eclipse. It describes various parameters pertaining to this eclipse.[4]
Eclipse seasonThis 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.
Related eclipsesEclipses in 1998
Metonic
Tzolkinex
Half-Saros
Tritos
Lunar Saros 147
Inex
Triad
Lunar eclipses of 1995–1998This 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] The penumbral lunar eclipse on August 8, 1998 occurs in the next lunar year eclipse set.
Saros 147This eclipse is a part of Saros series 147, repeating every 18 years, 11 days, and containing 70 events. The series started with a penumbral lunar eclipse on July 2, 1890. It contains partial eclipses from September 28, 2034 through May 27, 2431; total eclipses from June 6, 2449 through October 5, 2647; and a second set of partial eclipses from October 16, 2665 through May 1, 2990. The series ends at member 70 as a penumbral eclipse on July 28, 3145. The longest duration of totality will be produced by member 37 at 105 minutes, 18 seconds on August 1, 2539. All eclipses in this series occur at the Moon’s descending node of orbit.[6]
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 seriesThis 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.
Half-Saros cycleA 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 partial solar eclipses of Solar Saros 154.
See alsoReferences
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