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To Be Published in Observer's Handbook 2004, Royal Astronomical Society of Canada
During the year 2004, there will be two solar eclipses and two lunar eclipses:
2004 Apr 19: Partial Solar Eclipse
2004 May 04: Total Lunar Eclipse
2004 Oct 14: Partial Solar Eclipse
2004 Oct 28: Total Lunar Eclipse
Predictions and maps for the solar and lunar eclipses are presented in a number of figures linked to this document. World maps show the regions of visibility for each eclipse. The lunar eclipse diagrams also include the path of the Moon through Earth's shadows. Contact times for each principal phase are tabulated along with the magnitudes and geocentric coordinates of the Sun and Moon at greatest eclipse.
All times and dates used in this publication are in Universal Time or UT. This astronomically derived time system is colloquially referred to as Greenwich Mean Time or GMT. To learn more about UT and how to convert UT to your own local time, see Time Zones and Universal Time.
The first solar eclipse of 2004 is a southern hemisphere event visible from southern Africa and parts of Antarctica (Figure 1). Greatest eclipse takes place at 13:34:01 UT when the eclipse magnitude will reach 0.7357. The contact times of the Moon's penumbral shadow with Earth are as follows:
Partial Eclipse Begins: 11:29:55 UT
Partial Eclipse Ends: 15:38:36 UT
Local circumstances for a number of cities are given in Table 1. All times are provided in Universal Time. Sun's altitude and azimuth, the eclipse magnitude and obscuration are all listed for the instant of maximum eclipse.
This is the 65th eclipse of Saros series 119, an old series which produced its last central eclipse (annular) on 1950 Mar 18.
The series will continue to produce partial eclipses of decreasing magnitude until the final event on 2112 Jun 24.
2004 May 04: Total Lunar Eclipse
The first of two total lunar eclipses in 2004 is best seen from the Eastern Hemisphere.
The eclipse occurs 1 1/3 days before perigee so the Moon will appear rather large (33.1 arc-minutes).
During this event, the Moon is low on the ecliptic in western Libra just 1.5° south of the 2.8 magnitude star Zuben Elgenubi (Alpha Librae).
The Moon's path takes it through the southern part of Earth's umbral shadow.
Although the eclipse is not central, the total phase still lasts 1 hour 16 minutes.
The major phases of the eclipse are as follows:
At the instant of greatest eclipse (20:30 UT), the Moon will lie in the zenith for observers near northern Madagascar.
At this time, the umbral magnitude 1 peaks at 1.309 as the Moon's northern limb passes 2.5 arc-minutes south of the shadow's axis.
In contrast, the Moon's southern limb will lie 10.2 arc-minutes from the southern edge of the umbra and 35.6 arc-minutes from the shadow centre.
Thus, the southern sections of the Moon will appear much brighter than the northern part which will lie deeper in the shadow.
Since the Moon samples a large range of umbral depths during totality, its appearance will likely change dramatically with time.
However, it's impossible to predict the exact brightness distribution in the umbra so observers are encouraged to estimate the Danjon value at different times during totality (see section: Danjon Scale of Lunar Eclipse Brightness.
Note that it may also be necessary to assign different Danjon values to different portions of the Moon (i.e. - north vs. south).
During totality, the spring constellations will be well placed for viewing.
Antares (mv = +1.06) is 25° to the east of the eclipsed Moon, while Spica (mv = +0.98) is 22° west and Arcturus (mv = -0.05) is 37° to the northwest.
The planet Jupiter will appear low in the west in Leo.
The eclipse will be widely visible from the Europe, Africa, Asia and Australia.
North America will miss the entire event, but most of South America will witness the last stages of the eclipse which will already be in progress at moonrise.
Similarly, the Moon sets in eastern Asia and Australia during various stages of the eclipse.
Table 2 lists predicted umbral immersion and emersion times for twenty well-defined lunar craters.
The timing of craters is useful in determining the atmospheric enlargement of Earth's shadow (see section: Crater Timings During Lunar Eclipses ).
The second solar eclipse of 2004 is visible from the northern hemisphere.
Northeastern Asia, the Pacific Ocean and parts of Alaska will fall within the Moon's penumbral shadow (Figure 3).
Greatest eclipse takes place at 02:59:18 UT when the eclipse magnitude will reach 0.9270.
The contact times of the Moon's penumbral shadow with Earth are as follows:
Local circumstances for a number of cities are given in Table 3.
All times are provided in Universal Time.
The Sun's altitude and azimuth, the eclipse magnitude and obscuration are all listed for the instant of maximum eclipse.
Of special note to North Americans is that both Hawaii and Alaska will witness this eclipse at sunset.
This is the 54th eclipse of Saros series 124, another old series which produced its last central eclipse on 1986 Oct 03.
The event was an unusual beaded annular eclipse with a very short path just off the west coast of Iceland.
Saros 124 will continue to produce partial eclipses of decreasing magnitude until 2347 May 11.
2004 Oct 28: Total Lunar Eclipse
The last eclipse of the year is another total lunar eclipse.
This time, the event will be well placed for North Americans.
The eclipse occurs at the ascending node of Luna's orbit in southern Aries.
Since the Moon is 5.6 days shy of apogee, it will appear 7% smaller (= 30.6 arc-minutes) than it was during May's eclipse.
The Moon's trajectory takes it deep into the northern umbral shadow resulting in a total eclipse which lasts 1 hour 21 minutes.
At mid-totality, the Moon's southern limb is a mere 0.7 arc-minutes from the umbra's centre.
In contrast, the northern limb is 9.5 arc-minutes from the umbra's edge and 31.3 arc-minutes from its centre.
Since different parts of the Moon will probe radically different portions of Earth's umbral shadow, a large variation in shadow brightness can be expected.
The totally eclipsed Moon will appear to have a bright rim along its northern edge.
Observers are encouraged to estimate the Danjon value at mid-totality (see section: Danjon Scale of Lunar Eclipse Brightness).
The penumbral phase of October's eclipse begins at 00:06 UT, but most observers will not be able to visually detect the shadow until about 00:45 UT.
A timetable for the major phases of the eclipse is as follows:
The Moon's path through Earth's shadows as well as a map illustrating worldwide visibility of the event is shown in Figure 4.
At the instant of mid-totality (03:04 UT), the Moon will stand near the zenith for observers in the southern Caribbean.
At that time, the umbral eclipse magnitude will be 1.313.
Most of North America will be treated to the entire eclipse.
However, the penumbral phases will already be in progress at moonrise for observers in the western States and Canada.
Eastern Alaska will catch totality just after moonrise, but observers in the southwestern corner of the state will see the Moon rise already in total eclipse.
Various stages of the eclipse are in progress at moonset for observers throughout much of Asia and Africa.
However, eastern and southeast Asia as well as Australia will miss the entire event because it begins after moonset.
Table 4 lists predicted umbral immersion and emersion times for twenty well-defined lunar craters.
The timing of craters is useful in determining the atmospheric enlargement of Earth's shadow (see section: Crater Timings During Lunar Eclipses).
For a special NASA web page on this event, see:
Total Lunar Eclipse of Oct 27-28, 2004.
1Umbral magnitude of a lunar eclipse is defined as the fraction of the Moon's diameter covered by the umbral shadow. The magnitude is less than 1.0 for partial eclipses, and ≥1.0 for total eclipses.
Penumbral Eclipse Begins: 17:50:53 UT
Partial Eclipse Begins: 18:48:20 UT
Total Eclipse Begins: 19:52:07 UT
Greatest Eclipse: 20:30:16 UT
Total Eclipse Ends: 21:08:27 UT
Partial Eclipse Ends: 22:12:15 UT
Penumbral Eclipse Ends: 23:09:36 UT
2004 Oct 14: Partial Solar Eclipse
Partial Eclipse Begins: 00:54:38 UT
Partial Eclipse Ends: 05:04:17 UT
Penumbral Eclipse Begins: 00:05:35 UT
Partial Eclipse Begins: 01:14:25 UT
Total Eclipse Begins: 02:23:28 UT
Greatest Eclipse: 03:04:06 UT
Total Eclipse Ends: 03:44:43 UT
Partial Eclipse Ends: 04:53:44 UT
Penumbral Eclipse Ends: 06:02:44 UT
Key to Solar Eclipse Maps
Key to Lunar Eclipse Maps
Danjon Scale of Lunar Eclipse Brightness
h = 15 (GST + UT - ra ) + l
a = ArcSin [ Sin d Sin f + Cos d Cos h Cos f ]
A = ArcTan [ - (Cos d Sin h) / (Sin d Cos f - Cos d Cos h Sin f) ]
where:
h = Hour Angle of Sun or Moon
a = Altitude
A = Azimuth
GST = Greenwich Sidereal Time at 0:00 UT
UT = Universal Time
ra = Right Ascension of Sun or Moon
d = Declination of Sun or Moon
l = Observer's Longitude (East +, West -)
f = Observer's Latitude (North +, South -)
During the eclipses of 2004, the values for GST and the geocentric Right Ascension and Declination of the Sun or the Moon (at greatest eclipse) are as follows:
Eclipse Date GST ra d
Partial Solar 2004 Apr 19 13.866 1.850 11.411
Total Lunar 2004 May 04 14.871 14.807 -16.540
Partial Solar 2004 Oct 14 1.533 13.300 -8.236
Total Lunar 2004 Oct 28 2.454 2.176 13.441
2005 Apr 08: Hybrid Solar Eclipse
2005 Apr 24: Penumbral Lunar Eclipse
2005 Oct 03: Annular Solar Eclipse
2005 Oct 17: Partial Lunar Eclipse
A full report Eclipses During 2005 will be published in the Observer's Handbook 2005.
Special bulletins containing detailed predictions and meteorological data for future solar eclipses of interest are prepared by F. Espenak and J. Anderson, and are published through NASA's Publication series. The bulletins are provided as a public service to both the professional and lay communities, including educators and the media. A list of currently available bulletins and an order form can be found at:
Single copies of the eclipse bulletins are available at no cost by sending a 9 by 12 inch self-addressed envelope stamped with postage for 11 ounces (310 grams. Please print the eclipse year on the envelope's lower left corner. Use stamps only, since cash or checks cannot be accepted. Requests from outside the U. S. and Canada may send ten international postal coupons. Mail requests to: Fred Espenak, NASA/Goddard Space Flight Center, Code 693, Greenbelt, Maryland 20771, USA. The NASA eclipse bulletins are also available over the Internet, including out-of-print bulletins. Using a Web browser, they can be read or downloaded via the World-Wide Web from the GSFC/SDAC (Solar Data Analysis Center) eclipse page:
The original Microsoft Word text files and PICT figures (Macintosh format) are also available via anonymous ftp. They are stored as BinHex-encoded, StuffIt-compressed Mac folders with .hqx suffixes. For PC's, the text is available in a zip-compressed format in files with the .zip suffix. There are three sub directories for figures (GIF format), maps (JPEG format), and tables.
A special solar and lunar eclipse web site is available via the Internet at:
The site features predictions and maps for all solar and lunar eclipses well into the 21st century. Special emphasis is placed on eclipses occurring during the next two years with detailed path maps, tables, graphs and meteorological data. Additional catalogs list every solar and lunar eclipse over a 5000 year period.
All eclipse predictions were generated on an Appple G4 iMac computer using algorithms developed from the Explanatory Supplement [1974] with additional algorithms from Meeus, Grosjean, and Vanderleen [1966]. The solar and lunar ephemerides were generated from Newcomb and the Improved Lunar Ephemeris. A correction of -0.6" was added to the Moon's ecliptic latitude to account for the difference between the Moon's centre of mass and centre of figure. For partial solar eclipses, the value used for the Moon's radius is k=0.2724880. For lunar eclipses, the diameter of the umbral shadow was enlarged by 2% to compensate for Earth's atmosphere and the effects of oblateness have been included. Text and table composition was done on a Macintosh using Microsoft Word. Additional figure annotation was performed with Claris MacDraw Pro.
All calculations, diagrams, tables and opinions presented in this paper are those of the author and he assumes full responsibility for their accuracy.
Special thanks to National Space Club summer intern Lauren Williams for her valuable assistance in preparing this web page. (July 2003)
Webmaster: Fred Espenak Planteary Systems Laboratory - Code 693 Email: fred.espenak@nasa.gov NASA/Goddard Space Flight Center, Greenbelt, MD 20771, USA |
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Last revised: 2007 Jun 18 - F. Espenak
