Solar Eclipse Prime Page

Annular Solar Eclipse of 1981 Feb 04

Fred Espenak

Introduction


The Annular Solar Eclipse of 1981 Feb 04 is visible from the following geographic regions:

  • Partial Eclipse: Australia, New Zealand, Antarctica, west South America
  • Annular Eclipse: Tasmania, New Zealand, south Pacific

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 1981 Feb 04 at 22:09:24 TD (22:08:32 UT1). This is 4.0 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 719.

The eclipse belongs to Saros 140 and is number 27 of 71 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.

The annular solar eclipse of 1981 Feb 04 is preceded two weeks earlier by a penumbral lunar eclipse on 1981 Jan 20.

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 51.5 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 Annular Solar Eclipse of 1981 Feb 04 .


Eclipse Data: Annular Solar Eclipse of 1981 Feb 04

Eclipse Characteristics
Parameter Value
Eclipse Magnitude 0.99375
Eclipse Obscuration 0.98754
Gamma-0.48375
Conjunction Times
Event Calendar Date & Time Julian Date
Greatest Eclipse 1981 Feb 04 at 22:09:23.5 TD (22:08:32.1 UT1) 2444640.422593
Ecliptic Conjunction 1981 Feb 04 at 22:14:36.9 TD (22:13:45.4 UT1) 2444640.426220
Equatorial Conjunction 1981 Feb 04 at 21:58:30.2 TD (21:57:38.7 UT1) 2444640.415032
Geocentric Coordinates of Sun and Moon
1981 Feb 04 at 22:09:23.5 TD (22:08:32.1 UT1)
Coordinate Sun Moon
Right Ascension21h13m55.8s21h14m19.6s
Declination-16°02'03.1"-16°29'36.7"
Semi-Diameter 16'13.2" 15'53.6"
Eq. Hor. Parallax 08.9" 0°58'19.6"
Geocentric Libration of Moon
Angle Value
l -4.9°
b 0.6°
c -18.9°
Prediction Paramaters
Paramater Value
Ephemerides JPL DE406
ΔT 51.5 s
k (penumbra) 0.2725076
k (umbra) 0.2722810
Saros Series 140 (27/71)

Explanation of Solar Eclipse Data Tables

Penumbral Shadow Contacts and Extremes: Annular Solar Eclipse of 1981 Feb 04

Contacts of Penumbral Shadow with Earth
Contact Event Contact Time
TD
Time
UT1
Latitude Longitude
First External ContactP119:28:42.219:27:50.728°40.4'S152°28.9'E
Last External ContactP400:50:03.700:49:12.206°14.7'S097°00.1'W
Extreme Northern and Southern Path Limits of Penumbra
Contact Event Contact Time
TD
Time
UT1
Latitude Longitude
North Extreme Path Limit 1N120:12:33.620:11:42.107°44.2'S148°20.2'E
South Extreme Path Limit 1S100:06:08.000:05:16.514°47.8'N092°09.8'W

Explanation of Penumbral Shadow Contacts and Extremes Tables

Umbral Shadow Contacts and Extremes: Annular Solar Eclipse of 1981 Feb 04

Contacts of Umbral Shadow with Earth
Contact Event Contact Time
TD
Time
UT1
Latitude Longitude
First External ContactU120:33:25.020:32:33.538°43.1'S132°01.6'E
First Internal ContactU220:34:54.920:34:03.439°04.6'S131°28.7'E
Last Internal ContactU323:44:02.323:43:10.816°49.6'S077°18.8'W
Last External ContactU423:45:26.323:44:34.916°29.0'S077°46.3'W
Extreme Northern and Southern Path Limits of Umbra
Contact Event Contact Time
TD
Time
UT1
Latitude Longitude
North Extreme Path Limit 1N120:33:44.020:32:52.538°31.8'S132°02.4'E
South Extreme Path Limit 1S120:34:36.020:33:44.539°15.8'S131°27.9'E
North Extreme Path Limit 2N223:45:08.523:44:17.016°18.1'S077°45.2'W
South Extreme Path Limit 2S223:44:20.123:43:28.617°00.4'S077°19.8'W

Explanation of Umbral Shadow Contacts and Extremes Tables

Central Line Extremes and Duration: Annular Solar Eclipse of 1981 Feb 04

Extreme Limits of the Central Line
Contact Event Contact Time
TD
Time
UT1
Latitude Longitude
Extreme Central Line Limit 1C120:34:09.920:33:18.438°53.8'S131°45.2'E
Extreme Central Line Limit 2C223:44:44.423:43:52.916°39.2'S077°32.6'W

Explanation of Central Line Extremes Table

Greatest Eclipse and Greatest Duration
Event Time
TD
Time
UT1
Latitude Longitude Sun
Altitude
Sun
Azimuth
Path Width Central
Duration
Greatest Eclipse22:09:23.522:08:32.144°26.0'S140°58.9'W 60.8° 344.3° 25.0 km00m33.14s
Greatest Duration20:34:09.920:33:18.438°53.8'S131°45.2'E 0.0° 110.8° 93.7 km01m13.32s

Explanation of Greatest Eclipse and Greatest Duration

Polynomial Besselian Elements: Annular Solar Eclipse of 1981 Feb 04

Polynomial Besselian Elements
1981 Feb 04 at 22:00:00.0 TD (=t0)
n x y d l1 l2 μ
0 0.01345 -0.49118 -16.0350 0.55204 0.00586 146.4973
1 0.53928 0.11136 0.0123 -0.00012 -0.00012 15.0005
2 -0.00001 0.00014 0.0000 -0.00001 -0.00001 0.0000
3 -0.00001 -0.00000 - - - -
Tan ƒ1 0.0047423
Tan ƒ2 0.0047187

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 = 22.000

Explanation of Polynomial Besselian Elements

Links for the Annular Solar Eclipse of 1981 Feb 04

Links to Additional Solar Eclipse Information

Eclipse Predictions

Predictions for the Annular Solar Eclipse of 1981 Feb 04 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 51.5 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.