July 1916 lunar eclipse

July 1916 lunar eclipse
Partial eclipse
Date	15 July 1916
Gamma	−0.59568
Magnitude	0.79437
Saros cycle	118 (46 of 73)
Partiality	172 minutes, 30 seconds
Penumbral	292 minutes, 24 seconds
P1
Contacts (UTC)
P1	02:19:36
U1	03:19:33
Greatest	04:45:48
U4	06:12:03
P4	07:12:00
	← January 1916 January 1917 →

A partial lunar eclipse took place on 15 July 1916. The moon was strikingly shadowed in this deep partial eclipse which lasted 2 hours and 53 minutes, with 79% of the moon in darkness at maximum.

Observations

The Ross Sea party was a component of Sir Ernest Shackleton's Imperial Trans-Antarctic Expedition of 1914–17. Five men were stranded not far away from Cape Evans. There was sea ice between them and the relative safety of the hut on Cape Evans. On 8 May two of the men, Aeneas Mackintosh and Victor Hayward, decided to make an attempt to reach the hut. Soon after they set out, a blizzard hit. When the weather cleared up, the remaining men tried to look for them, but realized that the ice was far too thin to cross, and that their friends had been lost. Now they knew that they should wait for a thicker ice and for the full moon to attempt the crossing. Having the full moon was essential, because during polar night the moon is the only source of natural light other than the extremely dim light of the stars.

The weather did not cooperate during the full moon of June, but on 15 July, everything seemed to be just right: calm weather, thick ice, clear skies and a full moon. The men started their journey in the morning. When the moon rose, however, the men were surprised to find it was about to be eclipsed. Ernest Wild wrote later:

"I thought we were going to be left in darkness but a very little bit of the rim remained to light us..."

Although the eclipse continued for a few hours, the men were fortunate because it was only a partial eclipse. They reached Cape Evans later on the same day.^[1]

Visibility

Related eclipses

Lunar eclipses of 1915-1918

Lunar eclipse series sets from 1933–1936
Descending node			Ascending node
Saros	Date Viewing	Type Chart	Saros	Date Viewing	Type Chart
103	1915 Jan 31	Penumbral	108	1915 Jul 26	Penumbral
113	1916 Jan 20	Partial	118	1916 Jul 15	Partial
123	1917 Jan 08	Total	128	1917 Jul 04	Total
133	1917 Dec 28	Total	138	1918 Jun 24	Partial
143	1918 Dec 17	Penumbral

Half-Saros cycle

A lunar eclipse will be preceded and followed by solar eclipses by 9 years and 5.5 days (a half saros).^[2] This lunar eclipse is related to two annular solar eclipses of Solar Saros 125.

July 10, 1907	July 20, 1925

Notes

^ Richard McElrea; David L. Harrowfield (2004). Polar castaways: the Ross Sea Party (1914–17) of Sir Ernest Shackleton. Canterbury University Press. p. 206. ISBN 978-0-7735-2825-3.
^ Mathematical Astronomy Morsels, Jean Meeus, p.110, Chapter 18, The half-saros