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VI/97 Solar and Lunar Eclipses: 1996-2020 (Espenak, 1997)
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Catalog of Solar and Lunar Eclipses: 1996-2020 A.D.
Espenak, F.
<Bull. Inf. CDS (in press) (1999)>
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ADC_Keywords: Sun; Solar system
Description:
Solar Eclipses -
During the twenty-five year period 1996-2020, some portion of the Moon's
shadow will sweep across the Earth a total of fifty-six times. Twenty-one
of these events result in partial solar eclipses, seventeen of them are
annular eclipses, sixteen more are total eclipses and the remaining two
are both annular and total along sections of their narrow paths.
Local circumstances at the instant of greatest eclipse1 for every event
during this quarter century period are presented in solar.dat. The date and
Universal Time of the instant of greatest eclipse are found in the first
two columns. The eclipse type is given (T=Total, A=Annular, AT=Annular/Total
or P=Partial) along with the Saros series, as defined by van den Bergh
(1955). The magnitude of the eclipse is defined as the fraction of the
Sun's diameter obscured at greatest eclipse. The latitude and longitude of
the umbra are given for the instant of greatest eclipse, along with the
Sun's altitude, the width of the path (kilometers) and the duration of
totality or annularity. For partial eclipses, the latitude and longitude
of the point closest to the umbra's axis at the instant of greatest eclipse
are listed. The altitude of the Sun at this location is 0 degrees.
Note: Greatest eclipse is defined as the instant when the axis of the
Moon's shadow passes closest to the Earth's center. For total eclipses,
the instant of greatest eclipse is virtually identical to the instants
of greatest magnitude and greatest duration. However, for annular eclipses,
the instant of greatest duration may occur at either the time of greatest
eclipse or near the sunrise and sunset points of the eclipse path.
Lunar Eclipses -
During the twenty-five year period 1996-2020, the Moon will swing through
some portion of Earth's shadow a total of fifty-eight times. Twenty-three
of these events result in penumbral lunar eclipses, twelve of them are
partial (umbral) eclipses, twenty-three more are total lunar eclipses.
Local circumstances at the instant of greatest eclipse1 for every event
during this quarter century period are presented in Table 1. The date and
Universal Time of the instant of greatest eclipse are found in the first
two columns. The eclipse type is given (T=Total, P=Partial [Umbral], or
P=Penumbral) along with the Saros series, as defined by van den Bergh
(1955). The penumbral and umbral magnitudes of the eclipse are defined
as the fraction of the Moon's diameter obscured by either shadow at
greatest eclipse. The partial and total semi-durations of the eclipse
along with the Greenwich Siderial Time at midnight, and the Moon's
Right Ascension and Declination are listed.
The start and end times of the partial eclipse can be calculated by
respectively subtracting and adding the partial semi-duration (i.e. - Par.
SDur) to the instant of greatest eclipse. Likewise, the start and end times
of the total eclipse can be calculated by respectively subtracting and
adding the total semi-duration (i.e. - Total SDur) to the instant of
greatest eclipse.
Note: Greatest eclipse is defined as the instant when the Moon passes
closest to the axis of Earth's shadow(s). This marks the instant when the
Moon is deepest in Earth's shadow(s).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
solar.dat 73 56 Solar: Local Circumstances at Greatest Eclipse
lunar.dat 77 58 Lunar: Local Circumstances at Greatest Eclipse
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See also:
http://sunearth.gsfc.nasa.gov/eclipse/eclipse.html
Byte-by-byte Description of file: solar.dat
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Bytes Format Units Label Explanations
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1- 4 I4 yr Year Calendar Year (Gregorian) at instant of
Greatest Eclipse
6- 8 A3 --- Month Calendar Month (Gregorian) at instant of
Greatest Eclipse
10- 11 I2 d Day Calendar Day (Gregorian) at instant of
Greatest Eclipse
14- 15 I2 h Hour Hour (UT) of Greatest Eclipse
16 A1 --- colon [:] Hour/Minute separator
17- 18 I2 min Minute Minute of hour of Greatest Eclipse
22- 23 A2 --- Type *[PTA ] Type of eclipse
25- 27 I3 --- Saros Saros series of eclipse
30- 35 F6.3 --- Gamma Distance of the shadow cone axis from the
center of Earth (units of equatorial radii)
38- 42 F5.3 --- Magnitude Fraction of Sun's diameter obscured by Moon
45- 48 F4.1 deg Lat Latitude where greatest eclipse is seen
49 A1 --- LatHemi [NS] Latitude hemisphere (North or South)
51- 55 F5.1 deg Long Longitude where greatest eclipse is seen
56 A1 --- LongHemi [EW] Longitude hemisphere (East or West)
59- 60 I2 deg Alt Sun's altitude at greatest eclipse
63- 65 I3 km Width ?Width of the path of totality or annularity
at greatest eclipse
68- 69 I2 min DurMin ?Central duration of total or annular phase
at greatest eclipse (minutes)
70 A1 --- m [m ] Minutes label
71- 72 I2 s DurSec ?Central duration of total or annular phase
at greatest eclipse (seconds)
73 A1 --- s [s ] Seconds label
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Note on Type:
Type of eclipse where:
T = Total Eclipse
A = Annular Eclipse
AT = Annular/Total Eclipse
P = Partial Eclipse
Byte-by-byte Description of file: lunar.dat
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Bytes Format Units Label Explanations
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1- 4 I4 yr Year Calendar Year (Gregorian) at instant of
Greatest Eclipse
6- 8 A3 --- Month Calendar Month (Gregorian) at instant of
Greatest Eclipse
10- 11 I2 d Day Calendar Day (Gregorian) at instant of
Greatest Eclipse
14- 15 I2 h Hour Hour (UT) of Greatest Eclipse
16 A1 --- colon [:] Hour/Minute separator
17- 18 I2 min Minute Minute of hour of Greatest Eclipse
21 A1 --- Type *[PTU ] Type of eclipse
22 A1 --- n_Type *[+-b ] Note on type
24- 26 I3 --- Saros Saros series of eclipse
29- 34 F6.3 --- Gamma Distance of Moon from the axis of Earth's
shadow cone (units of equatorial radii)
37- 41 F5.3 --- PenMag Fraction of Moon's diameter obscured by
the penumbra
43- 48 F6.3 --- UmbMag Fraction of Moon's diameter obscured by
the umbra
50- 52 I3 min ParSDur ?Semi-duration of partial (umbral) eclipse
53 A1 --- mP [m ] Minutes label
56- 57 I2 min TotSDur ?Semi-duration of total (umbral) eclipse
58 A1 --- mT [m ] Minutes label
61- 64 F4.1 h GSTO Greenwich Siderial Time at 00:00 U.T.
67- 71 F5.2 h RA Geocentric Right Ascension of the Moon
at greatest eclipse
73- 77 F5.1 deg Dec Geocentric Declination of the Moon
at greatest eclipse
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Note on Type:
T = Total Eclipse
U = Partial (Umbral) Eclipse
P = Penumbral Eclipse
Note on n_Type:
"m" = Middle eclipse of Saros series
"+" = Central eclipse (Moon north of axis)
"-" = Central eclipse (Moon south of axis)
b = first penumbral eclipse of a new saros series ("b" = beginning)
c = central total eclipse (Tc)
Notes:
The altitude 'a' and azimuth 'A' of the Moon during any phase of an eclipse
depends on the time and the observer's geographic coordinates. Neglecting
the effects of atmospheric refraction and lunar parallax, 'a'
and 'A' are calculated as follows:
h = 15 (GST0 + 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
GST0 = 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 -)
References:
Espenak, F. 1989, Fifty Year Canon of Lunar Eclipses: 1986 - 2035,
NASA Reference Publication 1216
Espenak F. 1987. Fifty Year Canon of Solar Eclipses: 1986 - 2035,
NASA Reference Publication 1178 (1987)
van den Bergh, G. 1955, Periodicity and Variation of Solar (and Lunar)
Eclipses, Tjeenk Willink, Haarlem, Netherlands
History:
03-Apr-1998: Data and documentation were copied from the author's web site.
The data tables were modified slightly to meet CDS/ADC
standard practice (e.g., deleted header and spacer records).
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(End) James E. Gass [ADC/SSDOO] 12-May-1998