Solar Eclipse Prime Page

Partial Solar Eclipse of 1721 Dec 19

Fred Espenak

Introduction

eclipse map


The Partial Solar Eclipse of 1721 Dec 19 is visible from the geographic regions shown on the map to the right. Click on the map to enlarge it. For an explanation of the features appearing in the map, see Key to Solar Eclipse Maps.

The instant of greatest eclipse takes place on 1721 Dec 19 at 00:31:50 TD (00:31:40 UT1). This is 0.8 days before the Moon reaches perigee. During the eclipse, the Sun is in the constellation Sagittarius. The synodic month in which the eclipse takes place has a Brown Lunation Number of -2486.

The eclipse belongs to Saros 108 and is number 66 of 76 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 is a very deep partial eclipse. It has an eclipse magnitude of 0.4172, while Gamma has a value of 1.3144.

The partial solar eclipse of 1721 Dec 19 is followed two weeks later by a total lunar eclipse on 1722 Jan 02.

Another solar eclipse occurs one synodic month after the 1721 Dec 19 eclipse. It is the partial solar eclipse of 1722 Jan 17.

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 9.8 seconds for this eclipse.

The following links provide maps and data for the eclipse.

The tables below contain detailed predictions and additional information on the Partial Solar Eclipse of 1721 Dec 19 .


Eclipse Data: Partial Solar Eclipse of 1721 Dec 19

Eclipse Characteristics
Parameter Value
Eclipse Magnitude 0.41722
Eclipse Obscuration 0.30447
Gamma 1.31443
Conjunction Times
Event Calendar Date and Time Julian Date
Greatest Eclipse 1721 Dec 19 at 00:31:50.3 TD (00:31:40.4 UT1) 2349994.521996
Ecliptic Conjunction 1721 Dec 19 at 00:18:44.1 TD (00:18:34.2 UT1) 2349994.512896
Equatorial Conjunction 1721 Dec 19 at 00:15:44.5 TD (00:15:34.6 UT1) 2349994.510818
Geocentric Coordinates of Sun and Moon
1721 Dec 19 at 00:31:50.3 TD (00:31:40.4 UT1)
Coordinate Sun Moon
Right Ascension17h47m31.3s17h48m12.0s
Declination-23°26'37.1"-22°06'59.2"
Semi-Diameter 16'15.7" 16'39.7"
Eq. Hor. Parallax 08.9" 1°01'08.8"
Geocentric Libration of Moon
Angle Value
l -1.6°
b -1.7°
c -0.3°
Prediction Paramaters
Paramater Value
Ephemerides JPL DE406
ΔT 9.8 s
k (penumbra) 0.2725076
k (umbra) 0.2722810
Saros Series 108 (66/76)

Explanation of Solar Eclipse Data Tables

Penumbral Shadow Contacts and Extremes: Partial Solar Eclipse of 1721 Dec 19

Contacts of Penumbral Shadow with Earth
Contact Event Contact Time
TD
Time
UT1
Latitude Longitude
First External ContactP123:09:16.523:09:06.656°41.5'N143°24.0'E
Last External ContactP401:54:29.401:54:19.546°25.4'N146°18.8'W
Extreme Northern and Southern Path Limits of Penumbra
Contact Event Contact Time
TD
Time
UT1
Latitude Longitude
North Extreme Path Limit 1N123:34:26.523:34:16.751°15.2'N128°31.4'E
South Extreme Path Limit 1S101:29:19.901:29:10.140°12.2'N134°24.6'W

Explanation of Penumbral Shadow Contacts and Extremes Tables

Polynomial Besselian Elements: Partial Solar Eclipse of 1721 Dec 19

Polynomial Besselian Elements
1721 Dec 19 at 01:00:00.0 TD (=t0)
n x y d l1 l2 μ
0 0.42438 1.27343 -23.4472 0.53970 -0.00643 195.6164
1 0.57532 -0.06793 -0.0007 -0.00006 -0.00006 14.9963
2 0.00001 0.00011 0.0000 -0.00001 -0.00001 -0.0000
3 -0.00001 0.00000 - - - -
Tan ƒ1 0.0047540
Tan ƒ2 0.0047303

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 = 1.000

Explanation of Polynomial Besselian Elements

Links for the Partial Solar Eclipse of 1721 Dec 19

Links to Additional Solar 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 Partial Solar Eclipse of 1721 Dec 19 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 9.8 seconds for this eclipse.

Acknowledgments

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

Permission is granted to reproduce eclipse data when accompanied by a link to this page and 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.