| Type: | total |
| Date: | May 4, 2004 |
| Gamma: | −0.3132 |
| Magnitude: | 1.3035 |
| Saros Ser: | 131 |
| Saros No: | 33 of 72 |
| Totality: | 75 minutes, 28 seconds |
| Partiality: | 203 minutes, 12 seconds |
| Penumbral: | 315 minutes, 43 seconds |
| P1: | 17:52:54 |
| U1: | 18:48:38 |
| U2: | 19:52:29 |
| Greatest: | 20:30:13 |
| U3: | 21:07:57 |
| U4: | 22:11:50 |
| P4: | 23:08:03 |
| Previous: | November 2003 |
| Next: | October 2004 |
A total lunar eclipse occurred at the Moon’s descending node of orbit on Tuesday, May 4, 2004,[1] with an umbral magnitude of 1.3035. A lunar eclipse occurs when the Moon moves into the Earth's shadow, causing the Moon to be darkened. A total lunar eclipse occurs when the Moon's near side entirely passes into the Earth's umbral shadow. 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. A total lunar eclipse can last up to nearly two hours, while a total solar eclipse lasts only a few minutes at any given place, because the Moon's shadow is smaller. Occurring about 1.2 days before perigee (on May 6, 2004, at 0:30 UTC), the Moon's apparent diameter was larger.[2]
This lunar eclipse is the third of a tetrad, with four total lunar eclipses in series, the others being on May 16, 2003; November 9, 2004; and October 28, 2004.
The eclipse was completely visible over much of Africa, eastern Europe, Antarctica, and Asia, central, and south Asia, seen rising over South America, western Europe, and west Africa and setting over east Asia and Australia.[3]
Shown below is a table displaying details about this particular solar eclipse. It describes various parameters pertaining to this eclipse.[4]
| Penumbral Magnitude | 2.26449 | |
| Umbral Magnitude | 1.30536 | |
| Gamma | −0.31320 | |
| Sun Right Ascension | 02h48m55.8s | |
| Sun Declination | +16°14'51.5" | |
| Sun Semi-Diameter | 15'51.5" | |
| Sun Equatorial Horizontal Parallax | 08.7" | |
| Moon Right Ascension | 14h48m25.1s | |
| Moon Declination | -16°32'22.6" | |
| Moon Semi-Diameter | 16'32.0" | |
| Moon Equatorial Horizontal Parallax | 1°00'40.8" | |
| ΔT | 64.5 s |
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.
A lunar eclipse will be preceded and followed by solar eclipses by 9 years and 5.5 days (a half saros).[5] This lunar eclipse is related to two annular solar eclipses of Solar Saros 138.