A partial lunar eclipse occurred at the Moon's ascending node of orbit on Monday, April 4, 1977, with an umbral magnitude of 0.1929. A lunar eclipse occurs when the Moon moves into the Earth's shadow, causing the Moon to be darkened. A partial lunar eclipse occurs when one part of the Moon is in the Earth's umbra, while the other part is in 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 1.7 days before perigee (on April 5, 1977, at 21:50 UTC), the Moon's apparent diameter was larger.
Visibility The eclipse was completely visible over much of North America, South America, and west Africa, seen rising over western North America and the central Pacific Ocean and setting over Africa, Europe and the Middle East.
Eclipse details Shown below is a table displaying details about this particular lunar eclipse. It describes various parameters pertaining to this eclipse.
+April 4, 1977 Lunar Eclipse Parameters Parameter Value Penumbral Magnitude 1.16570 Umbral Magnitude 0.19289 Gamma −0.91483 Sun Right Ascension 00h52m35.5s Sun Declination +05°37'56.4" Sun Semi-Diameter 15'59.4" Sun Equatorial Horizontal Parallax 08.8" Moon Right Ascension 12h51m29.8s Moon Declination -06°30'38.9" Moon Semi-Diameter 16'26.2" Moon Equatorial Horizontal Parallax 1°00'19.6" ΔT 47.8 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 April 1977 April 4Ascending node (full moon) April 18Descending node (new moon) Partial lunar eclipseLunar Saros 112 Annular solar eclipseSolar Saros 138
Related eclipses Eclipses in 1977 A partial lunar eclipse on April 4. An annular solar eclipse on April 18. A penumbral lunar eclipse on September 27. A total solar eclipse on October 12.
Metonic Preceded by: Lunar eclipse of June 15, 1973 Followed by: Lunar eclipse of January 20, 1981
Tzolkinex Preceded by: Lunar eclipse of February 21, 1970 Followed by: Lunar eclipse of May 15, 1984
Half-Saros Preceded by: Solar eclipse of March 28, 1968 Followed by: Solar eclipse of April 9, 1986
Tritos Preceded by: Lunar eclipse of May 4, 1966 Followed by: Lunar eclipse of March 3, 1988
Lunar Saros 112 Preceded by: Lunar eclipse of March 24, 1959 Followed by: Lunar eclipse of April 15, 1995
Inex Preceded by: Lunar eclipse of April 23, 1948 Followed by: Lunar eclipse of March 14, 2006
Triad Preceded by: Lunar eclipse of June 3, 1890 Followed by: Lunar eclipse of February 2, 2064
Lunar eclipses of 1977–1980
Saros 112
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 119. March 28, 1968April 9, 1986
See also List of lunar eclipses List of 20th-century lunar eclipses
Notes
External links