Solar Eclipse Prime Page

Partial Solar Eclipse of 1917 Jan 23

Fred Espenak

Introduction


The Partial Solar Eclipse of 1917 Jan 23 is visible from the following geographic regions:

  • Partial Eclipse: northeast Africa, Middle East, west Asia, east Europe

The map to the right depicts the geographic regions of eclipse visibility. 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 1917 Jan 23 at 07:28:31 TD (07:28:12 UT1). This is 0.2 days before the Moon reaches perigee. During the eclipse, the Sun is in the constellation Capricornus. The synodic month in which the eclipse takes place has a Brown Lunation Number of -73.

The eclipse belongs to Saros 149 and is number 15 of 71 eclipses in the series. All eclipses in this series occur at the Moon’s ascending node. The Moon moves southward with respect to the node with each succeeding eclipse in the series and gamma decreases.

This is a very deep partial eclipse. It has an eclipse magnitude of 0.7254, while Gamma has a value of 1.1508.

The partial solar eclipse of 1917 Jan 23 is preceded two weeks earlier by a total lunar eclipse on 1917 Jan 08.

Another solar eclipse occurs one synodic month before the 1917 Jan 23 eclipse. It is the partial solar eclipse of 1916 Dec 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 19.3 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 1917 Jan 23 .


Eclipse Data: Partial Solar Eclipse of 1917 Jan 23

Eclipse Characteristics
Parameter Value
Eclipse Magnitude 0.72542
Eclipse Obscuration 0.66081
Gamma 1.15085
Conjunction Times
Event Calendar Date & Time Julian Date
Greatest Eclipse 1917 Jan 23 at 07:28:31.3 TD (07:28:11.9 UT1) 2421251.811249
Ecliptic Conjunction 1917 Jan 23 at 07:39:57.6 TD (07:39:38.3 UT1) 2421251.819193
Equatorial Conjunction 1917 Jan 23 at 08:08:41.5 TD (08:08:22.2 UT1) 2421251.839146
Geocentric Coordinates of Sun and Moon
1917 Jan 23 at 07:28:31.3 TD (07:28:11.9 UT1)
Coordinate Sun Moon
Right Ascension20h20m08.5s20h18m33.1s
Declination-19°33'15.8"-18°26'25.7"
Semi-Diameter 16'14.8" 16'44.5"
Eq. Hor. Parallax 08.9" 1°01'26.6"
Geocentric Libration of Moon
Angle Value
l -0.7°
b -1.5°
c -11.6°
Prediction Paramaters
Paramater Value
Ephemerides JPL DE406
ΔT 19.3 s
k (penumbra) 0.2725076
k (umbra) 0.2722810
Saros Series 149 (15/71)

Explanation of Solar Eclipse Data Tables

Penumbral Shadow Contacts and Extremes: Partial Solar Eclipse of 1917 Jan 23

Contacts of Penumbral Shadow with Earth
Contact Event Contact Time
TD
Time
UT1
Latitude Longitude
First External ContactP105:43:32.405:43:13.128°01.1'N018°04.3'E
Last External ContactP409:13:12.809:12:53.560°27.6'N095°58.4'E
Extreme Northern and Southern Path Limits of Penumbra
Contact Event Contact Time
TD
Time
UT1
Latitude Longitude
North Extreme Path Limit 1N106:14:36.106:14:16.718°20.6'N006°10.2'E
South Extreme Path Limit 1S108:42:11.008:41:51.752°17.3'N115°10.6'E

Explanation of Penumbral Shadow Contacts and Extremes Tables

Polynomial Besselian Elements: Partial Solar Eclipse of 1917 Jan 23

Polynomial Besselian Elements
1917 Jan 23 at 07:00:00.0 TD (=t0)
n x y d l1 l2 μ
0 -0.63163 1.00111 -19.5615 0.53821 -0.00791 282.0280
1 0.55173 0.18689 0.0092 -0.00000 -0.00000 14.9987
2 -0.00001 0.00008 0.0000 -0.00001 -0.00001 0.0000
3 -0.00001 -0.00000 - - - -
Tan ƒ1 0.0047495
Tan ƒ2 0.0047258

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 = 7.000

Explanation of Polynomial Besselian Elements

Links for the Partial Solar Eclipse of 1917 Jan 23

Links to Additional Solar Eclipse Information

Eclipse Predictions

Predictions for the Partial Solar Eclipse of 1917 Jan 23 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 19.3 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.