en May 1920 lunar eclipse

May 1920 lunar eclipse
Total eclipse
	The Moon's hourly motion shown right to left
Date	May 3, 1920
Gamma	−0.3312
Magnitude	1.2194
Saros cycle	120 (53 of 84)
Totality	71 minutes, 31 seconds
Partiality	219 minutes, 39 seconds
Penumbral	360 minutes, 4 seconds
P1
Contacts (UTC)
P1	22:50:47
U1	0:00:56
U2	1:15:01
Greatest	1:50:47
U3	2:26:32
U4	3:40:36
P4	4:50:51
	← November 1919 October 1920 →

A total lunar eclipse occurred at the Moon’s ascending node of orbit on Monday, May 3, 1920,^[1] with an umbral magnitude of 1.2194. 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 only about 3.8 days before apogee (on May 6, 1920, at 21:00 UTC), the Moon's apparent diameter was smaller.^[2]

This lunar eclipse was the first of an almost tetrad, with the others being on October 27, 1920 (total); April 22, 1921 (total); and October 16, 1921 (partial).

Visibility

The eclipse was completely visible over South America, west and southern Africa, western Europe, and Antarctica, seen rising over much of North America and the eastern Pacific Ocean and setting over eastern Europe, east Africa, and the western half of Asia.^[3]

Eclipse details

Shown below is a table displaying details about this particular solar eclipse. It describes various parameters pertaining to this eclipse.^[4]

May 3, 1920 Lunar Eclipse Parameters
Parameter	Value
Penumbral Magnitude	2.28178
Umbral Magnitude	1.21939
Gamma	−0.33118
Sun Right Ascension	02h39m30.8s
Sun Declination	+15°32'26.3"
Sun Semi-Diameter	15'51.7"
Sun Equatorial Horizontal Parallax	08.7"
Moon Right Ascension	14h39m15.0s
Moon Declination	-15°50'11.0"
Moon Semi-Diameter	14'55.8"
Moon Equatorial Horizontal Parallax	0°54'47.6"
ΔT	21.5 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 May 1920
May 3 Ascending node (full moon)	May 18 Descending node (new moon)

Total lunar eclipse Lunar Saros 120	Partial solar eclipse Solar Saros 146

Related eclipses

Eclipses in 1920

Lunar eclipses of 1919–1922

Half-Saros cycle

A lunar eclipse will be preceded and followed by solar eclipses by 9 years and 5.5 days (a half saros).^[5] This lunar eclipse is related to two total solar eclipses of Solar Saros 127.