A penumbral lunar eclipse occurred at the MoonâÂÂs descending node of orbit on Thursday, January 18, 1973, with an umbral magnitude of âÂÂ0.1292. A lunar eclipse occurs when the Moon moves into the Earth's shadow, causing the Moon to be darkened. A penumbral lunar eclipse occurs when part or all of the Moon's near side passes into 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 2 days after perigee (on January 16, 1973, at 20:50 UTC), the Moon's apparent diameter was larger.
This eclipse was the first of four lunar eclipses in 1973, with the others occurring on June 15 (penumbral), July 15 (penumbral), and December 10 (partial).
The eclipse was completely visible over Europe, Africa, and Asia, seen rising over eastern North America and much of South America and setting over east Asia and Australia.
Shown below is a table displaying details about this particular solar eclipse. It describes various parameters pertaining to this eclipse.
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.
A lunar eclipse will be preceded and followed by solar eclipses by 9 years and 5.5 days (a half saros). This lunar eclipse is related to two partial solar eclipses of Solar Saros 150.