A penumbral lunar eclipse occurred at the Moon’s descending node of orbit on Wednesday, January 30, 1991, with an umbral magnitude of −0.1106. 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 1.9 days after perigee (on January 28, 1991, at 8:35 UTC), the Moon's apparent diameter was larger.
This eclipse was the first of four lunar eclipses in 1991, with the others occurring on June 27 (penumbral), July 26 (penumbral), and December 21 (partial).
Visibility The eclipse was completely visible over North and South America, seen rising over northeast Asia and the central Pacific Ocean and setting over much of Africa and Europe.
Eclipse details Shown below is a table displaying details about this particular solar eclipse. It describes various parameters pertaining to this eclipse.
+January 30, 1991 Lunar Eclipse Parameters Parameter Value Penumbral Magnitude 0.88079 Umbral Magnitude −0.11060 Gamma −1.07522 Sun Right Ascension 20h49m07.1s Sun Declination -17°47'12.6" Sun Semi-Diameter 16'14.2" Sun Equatorial Horizontal Parallax 08.9" Moon Right Ascension 08h47m30.0s Moon Declination +16°46'53.1" Moon Semi-Diameter 16'22.7" Moon Equatorial Horizontal Parallax 1°00'06.5" ΔT 57.6 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 January 1991 January 15Ascending node (new moon) January 30Descending node (full moon) Annular solar eclipseSolar Saros 131 Penumbral lunar eclipseLunar Saros 143
Related eclipses Eclipses in 1991 An annular solar eclipse on January 15. A penumbral lunar eclipse on January 30. A penumbral lunar eclipse on June 27. A total solar eclipse on July 11. A penumbral lunar eclipse on July 26. A partial lunar eclipse on December 21.
Metonic Preceded by: Lunar eclipse of April 14, 1987 Followed by: Lunar eclipse of November 18, 1994
Tzolkinex Preceded by: Lunar eclipse of December 20, 1983 Followed by: Lunar eclipse of March 13, 1998
Half-Saros Preceded by: Solar eclipse of January 25, 1982 Followed by: Solar eclipse of February 5, 2000
Tritos Preceded by: Lunar eclipse of March 1, 1980 Followed by: Lunar eclipse of December 30, 2001
Lunar Saros 143 Preceded by: Lunar eclipse of January 18, 1973 Followed by: Lunar eclipse of February 9, 2009
Inex Preceded by: Lunar eclipse of February 19, 1962 Followed by: Lunar eclipse of January 10, 2020
Triad Preceded by: Lunar eclipse of March 31, 1904 Followed by: Lunar eclipse of November 29, 2077
Lunar eclipses of 1988–1991
Saros 143
Tritos series
Inex series
Half-Saros cycle A lunar eclipse will be preceded and followed by solar eclipses by 9 years and 5.5 days (a half saros).Mathematical Astronomy Morsels, Jean Meeus, p.110, Chapter 18, The half-saros This lunar eclipse is related to two partial solar eclipses of Solar Saros 150.
January 25, 1982February 5, 2000
See also List of lunar eclipses List of 20th-century lunar eclipses
Notes
External links