Total Lunar Eclipse of -1270 Apr 09 (1271 Apr 09 BCE)

Fred Espenak

Introduction

The Total Lunar Eclipse of -1270 Apr 09 (1271 Apr 09 BCE) is visible from the geographic regions shown on the map to the right. The diagram above the map depicts the Moon's path with respect to Earth's umbral and penumbral shadows. Click on the figure to enlarge it. For an explanation of the features appearing in the figure, see Key to Lunar Eclipse Figures.

The instant of greatest eclipse takes place on -1270 Apr 09 at 20:07:59 TD (11:41:55 UT1). This is 1.6 days before the Moon reaches perigee. During the eclipse, the Moon is in the constellation Libra. The synodic month in which the eclipse takes place has a Brown Lunation Number of -39489.

The eclipse belongs to Saros 21 and is number 40 of 75 eclipses in the series. All eclipses in this series occur at the Moon’s descending node. The Moon moves northward with respect to the node with each succeeding eclipse in the series and gamma increases.

This total eclipse is central meaning the Moon’s disk actually passes through the axis of Earth’s umbral shadow. It has an umbral eclipse magnitude of 1.8276, and Gamma has a value of 0.0278. Because they are so deep, such eclipses typically have the longest total phases. In this case, the duration of totality lasts 100.1 minutes. That qualifies the eclipse as a member of a select class of exceptionally long total eclipses with durations exceeding 100 minutes.

The total lunar eclipse of -1270 Apr 09 is preceded two weeks earlier by a partial solar eclipse on -1270 Mar 25, and it is followed two weeks later by a partial solar eclipse on -1270 Apr 24.

These eclipses all take place during a single eclipse season.

The eclipse predictions are given in both Terrestrial Dynamical Time (TD) and Universal Time (UT1). The parameter ΔT is used to convert between these two times (i.e., UT1 = TD - ΔT). ΔT has a value of 30363.8 seconds for this eclipse. The uncertainty in ΔT is 1240.2 seconds corresponding to a standard error in longitude of the eclipse visibility zones of 5.18°.

The following links provide maps and data for the eclipse.

The tables below contain detailed predictions and additional information on the Total Lunar Eclipse of -1270 Apr 09 .

Eclipse Data: Total Lunar Eclipse of -1270 Apr 09

Eclipse Characteristics
Parameter Value
Penumbral Magnitude 2.78616
Umbral Magnitude 1.82755
Gamma 0.02775
Epsilon 0.0279°
Opposition Times
Event Calendar Date & Time Julian Date
Greatest Eclipse -1270 Apr 09 at 20:07:59.0 TD (11:41:55.3 UT1) 1257288.987445
Ecliptic Opposition -1270 Apr 09 at 20:07:41.7 TD (11:41:37.9 UT1) 1257288.987245
Equatorial Opposition -1270 Apr 09 at 20:06:21.1 TD (11:40:17.3 UT1) 1257288.986311
Geocentric Coordinates of Sun and Moon
-1270 Apr 09 at 20:07:59.0 TD (11:41:55.3 UT1)
Coordinate Sun Moon
Right Ascension00h26m15.2s12h26m18.5s
Declination+02°53'35.0"-02°52'07.1"
Semi-Diameter 15'46.7" 16'27.6"
Eq. Hor. Parallax 08.7" 1°00'24.7"
Geocentric Libration of Moon
Angle Value
l -2.7°
b 0.0°
c 22.1°
Earth's Shadows
Parameter Value
Penumbral Radius 1.2823°
Umbral Radius 0.7563°
Prediction Paramaters
Paramater Value
Ephemerides JPL DE406
ΔT 30363.8 s
Shadow Rule Danjon
Shadow Enlargement 1.010
Saros Series 21 (40/75)

Explanation of Lunar Eclipse Data Tables

Eclipse Contacts: Total Lunar Eclipse of -1270 Apr 09

Lunar Eclipse Contacts
Eclipse Event Contact Time
TD		 Time
UT1		 Zenith Latitude Zenith Longitude Position Angle Axis Distance
Penumbral BeginsP117:26:03.909:00:00.102°03.8'S135°21.1'W 300.4° 1.5556°
Partial BeginsU118:20:50.309:54:46.502°20.1'S148°35.4'W 300.9° 1.0300°
Total BeginsU219:17:56.710:51:53.002°37.2'S162°23.6'W 302.7° 0.4818°
Greatest EclipseGreatest20:07:59.011:41:55.302°52.1'S174°29.2'W 29.3° 0.0279°
Total EndsU320:58:02.112:31:58.303°07.1'S173°25.1'E 116.0° 0.4822°
Partial EndsU421:55:09.213:29:05.403°24.1'S159°36.9'E 117.8° 1.0314°
Penumbral EndsP422:49:50.314:23:46.503°40.4'S146°23.9'E 118.3° 1.5577°
Eclipse Durations
Eclipse Phase Duration
Penumbral (P4 - P1)05h23m46.4s
Partial (U4 - U1)03h34m18.9s
Total (U3 - U2)01h40m05.4s

Explanation of Lunar Eclipse Contacts Table

Polynomial Besselian Elements: Total Lunar Eclipse of -1270 Apr 09

Polynomial Besselian Elements
-1270 Apr 09 at 20:00:00.0 TD (=t0)
n x y d f1 f2 f3
0 -0.05323 0.06197 0.0505 1.28228 0.75631 0.27433
1 0.50290 -0.28262 0.0003 0.00031 0.00031 0.00008
2 0.00018 -0.00008 -0.0000 -0.00000 -0.00000 -0.00000
3 -0.00001 0.00001 - - - -

At time t1 (decimal hours), each besselian element is evaluated by:

x = x0 + x1*t + x2*t2 + x3*t3 (or x = Σ [xn*tn]; n = 0 to 3)

where: t = t1 - t0 (decimal hours) and t0 = 20.000

Explanation of Besselian Elements

Links for the Total Lunar Eclipse of -1270 Apr 09 (1271 Apr 09 BCE)

Links to Additional Lunar Eclipse Information

Calendar

The Gregorian calendar (also called the Western calendar) is internationally the most widely used civil calendar. It is named for Pope Gregory XIII, who introduced it in 1582. On this website, the Gregorian calendar is used for all calendar dates from 1582 Oct 15 onwards. Before that date, the Julian calendar is used. For more information on this topic, see Calendar Dates.

The Julian calendar does not include the year 0. Thus the year 1 BCE is followed by the year 1 CE (See: BCE/CE Dating Conventions). This is awkward for arithmetic calculations. Years in this catalog are numbered astronomically and include the year 0. Historians should note there is a difference of one year between astronomical dates and BCE dates. Thus, the astronomical year 0 corresponds to 1 BCE, and astronomical year -1 corresponds to 2 BCE, etc..

Eclipse Predictions

Predictions for the Total Lunar Eclipse of -1270 Apr 09 were generated using the JPL DE406 solar and lunar ephemerides. The lunar coordinates were calculated with respect to the Moon's Center of Mass. The predictions are given in both Terrestrial Dynamical Time (TD) and Universal Time (UT1). The parameter ΔT is used to convert between these two times (i.e., UT1 = TD - ΔT). ΔT has a value of 30363.8 seconds for this eclipse. The uncertainty in ΔT is 1240.2 seconds corresponding to a standard error in longitude of the eclipse visibility zones of 5.18°.

Acknowledgments

Some of the content on this web site is based on the book Thousand Year Canon of Lunar Eclipses 1501 to 2500. All eclipse calculations are by Fred Espenak, and he assumes full responsibility for their accuracy.

Permission is granted to reproduce this data when accompanied by an acknowledgment:

"Eclipse Predictions by Fred Espenak, www.EclipseWise.com"

The use of diagrams and maps is permitted provided that they are NOT altered (except for re-sizing) and the embedded credit line is NOT removed or covered.