April 1930 lunar eclipse

April 1930 lunar eclipse
Partial eclipse
The Moon's hourly motion shown right to left
DateApril 13, 1930
Gamma0.9545
Magnitude0.1065
Saros cycle111 (62 of 71)
Partiality73 minutes, 22 seconds
Penumbral267 minutes, 18 seconds
Contacts (UTC)
P13:44:47
U15:21:43
Greatest5:58:30
U46:35:04
P48:12:06
← November 1929
October 1930 →

A partial lunar eclipse occurred at the Moon’s descending node of orbit on Sunday, April 13, 1930,[1] with an umbral magnitude of 0.1065. 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 3.8 days after perigee (on April 9, 1930, at 11:20 UTC), the Moon's apparent diameter was larger.[2]

Visibility

The eclipse was completely visible over North and South America, seen rising over eastern Australia and the central Pacific Ocean and setting over much of Europe and Africa.[3]

Eclipse details

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

April 13, 1930 Lunar Eclipse Parameters
Parameter Value
Penumbral Magnitude 1.10669
Umbral Magnitude 0.10650
Gamma 0.95452
Sun Right Ascension 01h23m32.1s
Sun Declination +08°47'25.3"
Sun Semi-Diameter 15'56.9"
Sun Equatorial Horizontal Parallax 08.8"
Moon Right Ascension 13h25m16.0s
Moon Declination -07°57'49.4"
Moon Semi-Diameter 15'56.7"
Moon Equatorial Horizontal Parallax 0°58'31.2"
ΔT 24.1 s

Eclipse season

See also: Eclipse cycle

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 1930
April 13
Descending node (full moon)		 April 28
Ascending node (new moon)
Partial lunar eclipse
Lunar Saros 111		 Hybrid solar eclipse
Solar Saros 137

Eclipses in 1930

Metonic

Tzolkinex

Half-Saros

Tritos

Lunar Saros 111

Inex

Triad

Lunar eclipses of 1930–1933

This 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 eclipses on February 10, 1933 and August 5, 1933 occur in the next lunar year eclipse set.

Lunar eclipse series sets from 1930 to 1933
Descending node   Ascending node
Saros Date
Viewing 		Type
Chart 		Gamma Saros Date
Viewing 		Type
Chart 		Gamma
111 1930 Apr 13
 Partial
 0.9545 116 1930 Oct 07
 Partial
 −0.9812
121 1931 Apr 02
 Total
 0.2043 126 1931 Sep 26
 Total
 −0.2698
131 1932 Mar 22
 Partial
 −0.4956 136 1932 Sep 14
 Partial
 0.4664
141 1933 Mar 12
 Penumbral
 −1.2369 146 1933 Sep 04
 Penumbral
 1.1776

Saros 111

This eclipse is a part of Saros series 111, repeating every 18 years, 11 days, and containing 71 events. The series started with a penumbral lunar eclipse on June 10, 830 AD. It contains partial eclipses from September 14, 992 AD through April 8, 1335; total eclipses from April 19, 1353 through August 4, 1533; and a second set of partial eclipses from August 16, 1551 through April 23, 1948. The series ends at member 71 as a penumbral eclipse on July 19, 2092.

The longest duration of totality was produced by member 35 at 106 minutes, 14 seconds on June 12, 1443. All eclipses in this series occur at the Moon’s descending node of orbit.[6]

Greatest First
The greatest eclipse of the series occurred on 1443 Jun 12, lasting 106 minutes, 14 seconds.[7] Penumbral Partial Total Central
830 Jun 10
 992 Sep 14
 1353 Apr 19
 1389 May 10
Last
Central Total Partial Penumbral
1497 Jul 14
 1533 Aug 04
 1948 Apr 23
 2092 Jul 19

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.

Half-Saros cycle

A 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 total solar eclipses of Solar Saros 118.

April 8, 1921 April 19, 1939

See also

Notes

  1. ^ "April 12–13, 1930 Partial Lunar Eclipse". timeanddate. Retrieved 16 December 2024.
  2. ^ "Moon Distances for London, United Kingdom, England". timeanddate. Retrieved 16 December 2024.
  3. ^ "Partial Lunar Eclipse of 1930 Apr 13" (PDF). NASA. Retrieved 16 December 2024.
  4. ^ "Partial Lunar Eclipse of 1930 Apr 13". EclipseWise.com. Retrieved 16 December 2024.
  5. ^ van Gent, R.H. "Solar- and Lunar-Eclipse Predictions from Antiquity to the Present". A Catalogue of Eclipse Cycles. Utrecht University. Retrieved 6 October 2018.
  6. ^ "NASA - Catalog of Lunar Eclipses of Saros 111". eclipse.gsfc.nasa.gov.
  7. ^ Listing of Eclipses of series 111
  8. ^ Mathematical Astronomy Morsels, Jean Meeus, p.110, Chapter 18, The half-saros