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astronomy/generate/eclipse/readme_solar_eclipse.txt

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Eclipse Predictions by Fred Espenak, NASA's GSFC
Collected from:
https://web.archive.org/web/20080311001653/http://sunearth.gsfc.nasa.gov/eclipse/SEcat5/catalog.html
Key:
https://web.archive.org/web/20070820134803/http://sunearth.gsfc.nasa.gov/eclipse/SEcat5/catkey.html
Column Heading Definition/Description
1 Catalog Sequential number of the eclipse in the catalog links to
Number the map published in the
Five Millennium Canon of Solar Eclipses: -1999 to +3000.
2 Calendar Calendar Date at instant of Greatest Eclipse.
Date Gregorian Calendar is used for dates after 1582 Oct 15.
Julian Calendar is used for dates before 1582 Oct 04.
3 TD of Dynamical Time (TD) of Greatest Eclipse, the instant
Greatest when the axis of the Moon's shadow cone passes closest
Eclipse to Earth's center.
4 ΔT Delta T (ΔT) is the arithmetic difference between
Dynamical Time and Universal Time. It is a measure of
the accumulated clock error due to the variable
rotation period of Earth.
5 Luna Lunation Number is the number of synodic months since
Num New Moon of 2000 Jan 06. The Brown Lunation Number
can be determined by adding 953.
6 Saros Saros series number of eclipse.
Num (Each eclipse in a Saros is separated by an interval
of 18 years 11.3 days.)
7 Ecl. Eclipse Type where:
Type P = Partial Eclipse.
A = Annular Eclipse.
T = Total Eclipse.
H = Hybrid or Annular/Total Eclipse.
Second character in Eclipse Type:
"m" = Middle eclipse of Saros series.
"n" = Central eclipse with no northern limit.
"s" = Central eclipse with no southern limit.
"+" = Non-central eclipse with no northern limit.
"-" = Non-central eclipse with no southern limit.
"2" = Hybrid path begins total and ends annular.
"3" = Hybrid path begins annular and ends total.
"b" = Saros series begins (first eclipse in series).
"e" = Saros series ends (last eclipse in series).
8 Gamma Distance of the shadow cone axis from the center
of Earth (units of equatorial radii) at the
instant of greatest eclipse.
9 Ecl. Eclipse magnitude is the fraction of the Sun's
Mag. diameter obscured by the Moon. For annular, total and
hybrid eclipses, this value is actually the diameter
ratio of Moon/Sun.
10 Lat. Latitude where greatest eclipse is seen.
11 Long. Longitude where greatest eclipse is seen.
12 Sun Sun's altitude at greatest eclipse.
Alt
13 Sun Sun's azimuth at greatest eclipse.
Azm
14 Path Width of the path of totality or annularity
Width at greatest eclipse (kilometers).
15 Central Central Line Duration of total or annular phase
Dur. at greatest eclipse.