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The last eclipse of 2004 occurs on the evening of Wednesday, October 27 (in Europe, the eclipse occurs during the early morning hours of Thursday, October 28). This event is a total eclipse of the Moon which will be visible from North and South America as well as Europe, Africa and Antarctica. During such an eclipse, the Moon's disk can take on a dramatically colorful appearance from bright orange to blood red to dark brown and (rarely) very dark gray.
An eclipse of the Moon can only take place at Full Moon, and only if the Moon passes through some portion of Earth's shadow. The shadow is actually composed of two cone-shaped parts, one nested inside the other. The outer shadow or penumbra is a zone where Earth blocks some (but not all) of the Sun's rays. In contrast, the inner shadow or umbra is a region where Earth blocks all direct sunlight from reaching the Moon.
If the Moon passes through only part on the umbra, a partial eclipse is seen. However, if the entire Moon passes through the umbral shadow, then a total eclipse of the Moon occurs. For more information on how, what, why, where and when of lunar eclipses, see the special web page lunar eclipses for beginners.
The following diagrams show the Moon's path through Earth's shadows (higher resolution versions of the above figure). The times of major stages of the eclipse are given for a number of time zones in North America and Europe. Please choose the diagram for your own time zone. Each diagram is a GIF file with a size of about 32k.
Note that most of the USA is observing Daylight Saving Timeduring the eclipse. Arizona remains on Mountain Standard Time year-round and does not use Daylight Saving Time. To get eclipse times for Arizona, use the times for Pacific Daylight Time. The Navajo Nation, in northeastern Arizona, is currently on Mountain Daylight Time. Indiana has the most complex implementation of Daylight Saving Time. Most of Indiana (including state capital Indianapolis) remains on Eastern Standard Time all year long (use times listed for Central Daylight Time). Ten counties (five near Chicago, IL, and five near Evansville, IN) are in the Central Time Zone and use Central Daylight Time. Five other counties (near Cincinnati, OH, and Louisville, KY) are in the Eastern Time Zone and use Eastern Daylight Time.
Some people may be puzzled that the Moon's motion is from west to east (right to left) in these diagrams, instead of its daily east to west (left to right) motion in the sky. The Moon actually moves WEST to EAST (right to left in the Northern Hemisphere) with respect to the Earth's shadow and the stars.
October's lunar eclipse is well-placed for North and South America as well as western Europe and Africa. From the United States, the eastern two-thirds of the country will see the entire eclipse (weather permitting). In the western third of the USA, the faint penumbral phase begins before moonrise but this is the least interesting and dramatic part of the eclipse. The more important and photogenic partial and total phases will be visible from all of North America with the exception of Alaska. From the Alaskan panhandle, the partial phases begin at moonrise, but further west the Moon will rise during totality.
Canada also witnesses the entire eclipse as does Central and South America. From western Europe, the eclipse occurs during the early morning hours of Thursday, October 28. The Moon sets during totality from East Africa, the Middle East and central Asia. India and western China will only see the early penumbral stages before the Moon sets. Further east, none of the eclipse is visible from Japan, eastern China, southeast Asia, Indonesia, Australia or New Zealand.
| Key to Eclipse Visibility Map | |
|---|---|
| P1 | Penumbral eclipse begins (not visible to the eye) |
| U1 | Partial eclipse begins |
| U2 | Total eclipse begins |
| U3 | Total eclipse ends |
| U4 | Partial eclipse ends |
| P4 | Penumbral eclipse ends (not visible to the eye) |
The map above shows the geographic regions of visibility for each phase of the eclipse. The entire eclipse is visible from start to finish in the white (unshaded) portion of the map, while none of the eclipse can be seen from the dark gray areas.
For anyone located in the blue shaded region labeled Eclipse at Moonrise, this means that the Moon will rise while some phase of the eclipse is already in progress. The contact curves labeled P1, U1, U2, U3, U4, and P4 represent each phase of the eclipse (see the key above). If you are west (left) of a particular curve, that phase occurs before moonrise and you will not see it. However, if you are east (right) of a curve, that phase occurs after moonrise and you will see it (weather permitting).
For example, on the above map, southern California lies west (left) of the P1 curve (penumbral eclipse begins) and east (right) of the curve U1 (partial eclipse begins). This means that the penumbral eclipse begins before moonrise from southern California. However, the partial phases will be visible since they begin after moonrise in California.
For observers located within the second blue shaded region labeled Eclipse at Moonset, the situation is reversed. Here the Moon sets while some phase of the eclipse is still in progress. If you are east (right) of a particular curve (P1, U1, U2, U3, U4, or P4), that phase occurs after moonset and you will not see it. However, if you are west (left) of a contact curve, that phase occurs before moonset and you will see it (weather permitting).
All total eclipses start with a penumbral followed by a partial eclipse, and end with a partial followed by a penumbral eclipse (the total eclipse is sandwiched in the middle). Since the penumbral phases of the eclipse are so difficult to see, we will ignore them.
From start to finish, October's lunar eclipse lasts about three hours and forty minutes (not including the penumbral phases which are very difficult to see). The partial eclipse begins as the Moon's eastern edge slowly moves into the Earth's umbral shadow. During the partial phases, it takes just over an hour for the Moon's orbital motion to carry it entirely within the Earth's dark umbra. The color and brightness of the totally eclipsed can vary considerably from one eclipse to another. Dark eclipses are caused by volcanic dust which filters and blocks much of the light reaching the Moon. But since no major volcanic eruptions have taken place recently, the Moon will probably take on a vivid red or orange color during the total phase. After the total phase ends, it is once again followed by a partial eclipse as the Moon gradually leaves the umbral shadow.
The total phase of a lunar eclipse is called totality. At this time, the Moon is completely immersed within the Earth's dark umbral shadow. During the October 27-28 eclipse totality will last about 81 minutes. This is considerably shorter that the maximum duration possible of 1 hour and 47 minutes (see: Total Lunar Eclipse of July 16, 2000).
The major phases of the eclipse occur as follows (all times are GMT or Greenwich Mean Time). The partial eclipse commences with first umbral contact at 01:14 GMT. Totality begins at 02:23 GMT and lasts until 03:45 GMT. The partial phases end at 04:54 GMT. Eclipse times for time zones in the United States and Canada are shown in the following table.
| Total Lunar Eclipse of October 27, 2004 | ||||||||
|---|---|---|---|---|---|---|---|---|
| Americas | Europe, Africa & Middle East | |||||||
| Event | Time EDT | Time CDT | Time MDT | Time PDT | Time GMT | Time GMT+1 | Time GMT+2 | Time GMT+3 |
| Partial Eclipse Begins: | 21:14 (9:14 pm) | 20:14 (8:14 pm) | 19:14 (7:14 pm) | 18:14 (6:14 pm) | 01:14* | 02:14* | 03:14* | 04:14* |
| Total Eclipse Begins: | 22:23 (10:23 pm) | 21:23 (9:23 pm) | 20:23 (8:23 pm) | 19:23 (7:23 pm) | 02:23* | 03:23* | 04:23* | 05:23* |
| Mid-Eclipse: | 23:04 (11:04 pm) | 22:04 (10:04 pm) | 21:04 (9:04 pm) | 20:04 (8:04 pm) | 03:04* | 04:04* | 05:04* | 06:04* |
| Total Eclipse Ends: | 23:45 (11:45 pm) | 22:45 (10:45 pm) | 21:45 (9:45 pm) | 20:45 (8:45 pm) | 03:45* | 04:45* | 05:45* | 06:45* |
| Partial Eclipse Ends: | 00:54* | 23:54 (11:54 pm) | 22:54 (10:54 pm) | 21:54 (9:54 pm) | 04:54* | 05:54* | 06:54* | 07:54* |
| Key to Time Zones | |
|---|---|
| Zone | Description |
| EDT | Eastern Daylight Time (= GMT - 4 hours) |
| CDT | Central Daylight Time (= GMT - 5 hours) |
| MDT | Mountain Daylight Time (= GMT - 6 hours) |
| PDT | Pacific Daylight Time (= GMT - 7 hours) |
| GMT | Greenwich Mean Time |
| GMT+1 | Greenwich Mean Time + 1 Hour (= GMT + 1 hour) |
| GMT+2 | Greenwich Mean Time + 2 Hours (= GMT + 2 hours) |
| GMT+3 | Greenwich Mean Time + 3 Hours (= GMT + 3 hours) |
The table above provides times of the major eclipse phases for North American time zones, Greenwich Mean Time and several European time zones. Eclipse times for other time zones can be calculated by taking the difference between local time and Greenwich and adding it to the tabulated GMT times. If you live somewhere that does not use Daylight Saving Time in the summer months, you can convert the above times for your Time Zone from Daylight Saving Time to Standard Time simply by subtracting 1 hour. For more information, see Time Zones and Daylight Saving Time.
Note that most of the USA is observing Daylight Saving Time during the eclipse. Arizona remains on Mountain Standard Time year-round and does not use Daylight Saving Time. To get eclipse times for Arizona, use the times for Pacific Daylight Time. Indiana has the most complex implementation of Daylight Saving Time. Most of Indiana (including state capital Indianapolis) remains on Eastern Standard Time all year long (use times listed for Central Daylight Time). Ten counties (five near Chicago, IL, and five near Evansville, IN) are in the Central Time Zone and use Central Daylight Time. Five other counties (near Cincinnati, OH, and Louisville, KY) are in the Eastern Time Zone and use Eastern Daylight Time.
Please note that military style time (0-24 hours) is used for the principle stages of the eclipse. Times greater than 12:00 can be converted to civilian time by subtracting 12 hours. For example, the time 22:14 is equivalent to 10:14 pm (22:14 - 12:00 = 10:14 pm). For convenience, the corresponding civilian times (am & pm) are also included in parentheses below each military style time.
To determine the Moon's altitude at each stage of the eclipse as seen from your city or location, see Local Visibility of Lunar Eclipses. This web page offers several Microsoft Excel spread sheets which will calculate the Moon's altitude for all lunar eclipses from 1951 through 2050. All you need to do is enter your latitude and longitude into each spread sheet. You can also visit the U. S. Naval Observatory's Lunar Eclipse Computer.
Permission is freely granted to reproduce these eclipse diagrams when accompanied by the acknowledgment:
At the instant of mid-totality (03:04 GMT), the Moon will lie in the zenith for observers just to the east of the Caribbean. At this time, the umbral eclipse magnitude peaks at 1.313. From the diagram above, it is clear that the southern (bottom) edge of the Moon will dip much deeper into the Earth's shadow than will the northern (top) edge. Since the Earth's umbral shadow is darker in the center than at the edge, the Moon's appearance will likely change dramatically with time. A large variation in shadow brightness can be expected and observers are encouraged to estimate the Danjon value at different times during totality ( Danjon Brightness Scale). Note that it may also be necessary to assign different Danjon values to different portions of the Moon at different times.
This could be an excellent opportunity for budding astronomers and students to test their observing skills. Try recording your estimates of the Moon's brightness every ten minutes during totality using the Danjon Scale. Compare your results with your companions and classmates and discover how the Moon's appearance changes during the total eclipse. The brightness of the totally eclipsed Moon is very sensitive to the presence of volcanic dust in Earth's atmosphere. As part of a continuing research project, Dr. Richard Keen has been using reports of lunar eclipse brightnesses to calculate a history of optical thicknesses of volcanic dust layers (see: What Will 2004's Lunar Eclipses Look Like?). If you'd like to help Dr. Keen by making eclipse observations, you can contact him at Richard.Keen@Colorado.EDU.
The amount of dust in Earth's atmosphere also has an effect on the diameter of the umbral shadow. Amateur astronomers with telescopes can make careful timings of when some of the Moon's major craters enter or exit the umbra. Such observations are valuable in determining the enlargement of Earth's shadow. A table of crater predictions identifies twenty well-defined craters useful for this purpose. For more information, see: Crater Timings During Lunar Eclipses.
An eclipse of the Moon also presents a tempting subject to photograph. Since the Moon appears quite small in the sky, you'll need a fairly powerful telephoto lens (400 mm or more) or even a small telescope to attach to your camera. A typical 400 speed color film (either slides or negatives) is a good choice. For more information on equipment, film, recommended exposures and additional tips, see lunar eclipse photography.
Unlike solar eclipses, lunar eclipses are completely safe to watch. Protective filters are not necessary and neither is a telescope. A lunar eclipse can be observed with nothing more than the naked eye. However, a pair of binoculars will magnify the view and make the red coloration brighter and easier to see. A standard pair of 7x35 or 7x50 binoculars works fine.
During totality, the fall and winter constellations will be well placed for viewing. The Moon will be in southern Aries and crosses the ascending node of its orbit during the eclipse. The great square of Pegasus will be to the west of the Moon while Taurus and Orion lie to the east.
Although total eclipses of the Moon are of minor scientific value, they are remarkably beautiful events which do not require expensive equipment. They help to cultivate interest in science and astronomy in children and to provide a unique learning opportunity for families, students and teachers. To the nature lover and naturalist, the lunar eclipse can be appreciated and celebrated as an event which vividly illustrates our connection and place among the planets in the solar system. The three dimensional reality of our universe comes alive in a graceful celestial ballet as the Moon swings through the Earth's shadow. Hope for clear skies, dress warmly and enjoy the show!
During the five millennium period from 2000 BC through AD 3000, there are 7,718 eclipses1 of the Moon (including both partial and total eclipses). There are anywhere from 0 to 3 lunar eclipses (partial or total) each year. The last time three total lunar eclipses occurred in one calendar year was in 1982. Partial eclipses slightly outnumber total eclipses by 7 to 6.
1 Only eclipses where the Moon passes through Earth's umbral shadow are included in these values. A minor type of eclipse is the penumbral eclipse which occurs when the Moon passes through the Earth's faint penumbral shadow. Penumbral eclipses are rarely discernible to the naked eye and are of lesser importance than umbral eclipses.
The last total lunar eclipse visible from the entire continental United States occurred on Nov 09, 2003 . The last total eclipse occurred on May 04, 2004 and was seen from Europe, Africa and central Asia. North Americans will not have an opportunity to see another total lunar eclipse as well placed as the October 2004 event until Feb 21, 2008 .
The table below lists every lunar eclipse from 2003 through 2008. Click on the eclipse Date to see a map and diagram of an eclipse. Although penumbral lunar eclipses are included in this list, they are usually quite difficult to observe because of their subtlety. The penumbra is a partial shadow which still permits some direct sunlight to reach the Moon.
The Umbral Magnitude is the fraction on the Moon's diameter immersed in the umbra at maximum eclipse. For values of 1.0 or greater, the eclipse is total. For negative values, the eclipse is penumbral. The Total Duration is the duration of the total phase (total eclipses only).
| Lunar Eclipses: 2003 - 2008 | ||||
|---|---|---|---|---|
| Date | Eclipse Type | Umbral Magnitude | Total Duration | Geographic Region of Eclipse Visibility |
| 2003 May 16 | Total | 1.134 | 00h53m | c Pacific, Americas, Europe, Africa |
| 2003 Nov 09 | Total | 1.022 | 00h24m | Americas, Europe, Africa, c Asia |
| 2004 May 04 | Total | 1.309 | 01h16m | S. America, Europe, Africa, Asia, Aus. |
| 2004 Oct 28 | Total | 1.313 | 01h21m | Americas, Europe, Africa, c Asia |
| 2005 Apr 24 | Penumbral | -0.139 | - | e Asia, Aus., Pacific, Americas |
| 2005 Oct 17 | Partial | 0.068 | - | Asia, Aus., Pacific, North America |
| 2006 Mar 14 | Penumbral | -0.055 | - | Americas, Europe, Africa, Asia |
| 2006 Sep 07 | Partial | 0.189 | - | Europe, Africa, Asia, Aus. |
| 2007 Mar 03 | Total | 1.238 | 01h14m | Americas, Europe, Africa, Asia |
| 2007 Aug 28 | Total | 1.481 | 01h31m | e Asia, Aus., Pacific, Americas |
| 2008 Feb 21 | Total | 1.111 | 00h51m | c Pacific, Americas, Europe, Africa |
| 2008 Aug 16 | Partial | 0.813 | 03h09m | S. America, Europe, Africa, Asia, Aus. |
We will list links for live web coverage of the eclipse as they become available.
All eclipse calculations are by Fred Espenak, and he assumes full responsibility for their accuracy. Some of the information presented in this catalog is based on data originally published in Fifty Year Canon of Lunar Eclipses: 1986 - 2035.
Permission is freely granted to reproduce this data when accompanied by the following acknowledgment:
WebMaster: Fred Espenak e-mail: fred.espenak@nasa.gov Planetary Systems Branch - Code 693
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