A penumbral lunar eclipse occurred at the Moon's ascending node of orbit on Tuesday, January 20, 1981, with an umbral magnitude of −0.0192. It was a relatively rare total penumbral lunar eclipse, with the Moon passing entirely within the penumbral shadow without entering the darker umbral shadow.Total Penumbral Lunar Eclipses, Jean Meeus, June 1980 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 5.2 days after perigee (on January 15, 1981, at 3:35 UTC), the Moon's apparent diameter was larger.
Visibility The eclipse was completely visible over northeast Asia, North America, and western South America, seen rising over east Asia and eastern Australia and setting over eastern South America, west Africa and much of Europe.
Eclipse details Shown below is a table displaying details about this particular solar eclipse. It describes various parameters pertaining to this eclipse.
+January 20, 1981 Lunar Eclipse Parameters Parameter Value Penumbral Magnitude 1.01360 Umbral Magnitude −0.01916 Gamma −1.01421 Sun Right Ascension 20h09m28.4s Sun Declination -20°06'46.4" Sun Semi-Diameter 16'15.2" Sun Equatorial Horizontal Parallax 08.9" Moon Right Ascension 08h08m59.5s Moon Declination +19°08'35.7" Moon Semi-Diameter 15'44.3" Moon Equatorial Horizontal Parallax 0°57'45.5" ΔT 51.4 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–February 1981 January 20Ascending node (full moon) February 4Descending node (new moon) Penumbral lunar eclipseLunar Saros 114 Annular solar eclipseSolar Saros 140
Related eclipses Eclipses in 1981 A penumbral lunar eclipse on January 20. An annular solar eclipse on February 4. A partial lunar eclipse on July 17. A total solar eclipse on July 31.
Metonic Preceded by: Lunar eclipse of April 4, 1977 Followed by: Lunar eclipse of November 8, 1984
Tzolkinex Preceded by: Lunar eclipse of December 10, 1973 Followed by: Lunar eclipse of March 3, 1988
Half-Saros Preceded by: Solar eclipse of January 16, 1972 Followed by: Solar eclipse of January 26, 1990
Tritos Preceded by: Lunar eclipse of February 21, 1970 Followed by: Lunar eclipse of December 21, 1991
Lunar Saros 114 Preceded by: Lunar eclipse of January 9, 1963 Followed by: Lunar eclipse of January 31, 1999
Inex Preceded by: Lunar eclipse of February 11, 1952 Followed by: Lunar eclipse of December 31, 2009
Triad Preceded by: Lunar eclipse of March 21, 1894 Followed by: Lunar eclipse of November 21, 2067
Lunar eclipses of 1980–1984
Saros 114
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 annular solar eclipses of Solar Saros 121. January 16, 1972January 26, 1990
See also List of lunar eclipses List of 20th-century lunar eclipses
Notes
External links