Lunar month with the Sun one or two days before that evening ("e.g.", in the Islamic calendar). In ancient Egypt the lunar month began on the day when the waning moon could no longer be seen just before sunrise. Others use calculation, of varying degrees of sophistication, "e.g.", the Hebrew calendar or the ecclesiastical lunar calendar. Yet others run from full moon to full moon. Calendars count integer days, so months may be 29 or 30 days in length, in some regular or irregular sequence. In India the month from conjunction to conjunction is divided into thirty parts known as "tithis". The
April 2015 lunar eclipse 17 October 1529 (which lasted 1 minute and 42 seconds). Another shortest occurs on December 28 1917, lasting (11 minutes and 58 seconds). The next very short lunar totality will occur on 26 May 2021 (which will last 14 minutes and 24 seconds). This was the sixth total lunar eclipse out of nine with totality under 5 minutes in a five millennium period between 2,000 BC and 3,000 AD. However, due to the oblateness of the Earth, this lunar eclipse may have actually been (barely) a partial eclipse. This eclipsed moon was 12.9% smaller in apparent diameter than the supermoon