A penumbral lunar eclipse occurred at the MoonâÂÂs ascending node of orbit on Sunday, July 15, 1973, with an umbral magnitude of âÂÂ0.9581. 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 3 days after apogee (on July 12, 1973, at 22:45 UTC), the Moon's apparent diameter was smaller.
This eclipse was the third of four lunar eclipses in 1973, with the others occurring on January 18 (penumbral), June 15 (penumbral), and December 10 (partial).
This was the first lunar eclipse of Saros series 148.
The eclipse was completely visible over Australia, western North America, and Antarctica, seen rising over east Asia and setting over central North America and western South America.
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. The first and last eclipse in this sequence is separated by one synodic month.
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 155.