Solar Eclipse Prime Page

Total Solar Eclipse of 1977 Oct 12

Fred Espenak

Introduction


The Total Solar Eclipse of 1977 Oct 12 is visible from the following geographic regions:

  • Partial Eclipse: North America, northwest South America
  • Total Eclipse: Pacific, Colombia, Venezuela

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 1977 Oct 12 at 20:27:27 TD (20:26:39 UT1). This is 2.5 days before the Moon reaches perigee. During the eclipse, the Sun is in the constellation Virgo. The synodic month in which the eclipse takes place has a Brown Lunation Number of 678.

The eclipse belongs to Saros 143 and is number 21 of 72 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.

The total solar eclipse of 1977 Oct 12 is preceded two weeks earlier by a penumbral lunar eclipse on 1977 Sep 27.

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 48.3 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 Total Solar Eclipse of 1977 Oct 12 .


Eclipse Data: Total Solar Eclipse of 1977 Oct 12

Eclipse Characteristics
Parameter Value
Eclipse Magnitude 1.02694
Eclipse Obscuration 1.05462
Gamma 0.38363
Conjunction Times
Event Calendar Date & Time Julian Date
Greatest Eclipse 1977 Oct 12 at 20:27:27.3 TD (20:26:38.9 UT1) 2443429.351840
Ecliptic Conjunction 1977 Oct 12 at 20:31:29.7 TD (20:30:41.4 UT1) 2443429.354646
Equatorial Conjunction 1977 Oct 12 at 20:15:17.1 TD (20:14:28.8 UT1) 2443429.343389
Geocentric Coordinates of Sun and Moon
1977 Oct 12 at 20:27:27.3 TD (20:26:38.9 UT1)
Coordinate Sun Moon
Right Ascension13h11m36.7s13h12m03.0s
Declination-07°35'30.0"-07°13'40.8"
Semi-Diameter 16'01.8" 16'12.7"
Eq. Hor. Parallax 08.8" 0°59'29.8"
Geocentric Libration of Moon
Angle Value
l -4.0°
b -0.4°
c 23.7°
Prediction Paramaters
Paramater Value
Ephemerides JPL DE406
ΔT 48.3 s
k (penumbra) 0.2725076
k (umbra) 0.2722810
Saros Series 143 (21/72)

Explanation of Solar Eclipse Data Tables

Penumbral Shadow Contacts and Extremes: Total Solar Eclipse of 1977 Oct 12

Contacts of Penumbral Shadow with Earth
Contact Event Contact Time
TD
Time
UT1
Latitude Longitude
First External ContactP117:48:24.017:47:35.630°52.2'N175°44.0'W
First Internal ContactP220:01:41.420:00:53.072°43.9'N171°45.5'E
Last Internal ContactP320:53:33.820:52:45.440°33.7'N053°08.4'W
Last External ContactP423:06:31.523:05:43.102°11.1'S079°32.3'W
Extreme Northern and Southern Path Limits of Penumbra
Contact Event Contact Time
TD
Time
UT1
Latitude Longitude
North Extreme Path Limit 1N119:47:01.319:46:13.080°56.9'N153°15.9'W
South Extreme Path Limit 1S118:45:41.918:44:53.607°26.4'N166°23.2'E
North Extreme Path Limit 2N221:08:21.021:07:32.751°09.9'N059°49.5'W
South Extreme Path Limit 2S222:09:05.822:08:17.425°37.2'S061°47.6'W

Explanation of Penumbral Shadow Contacts and Extremes Tables

Umbral Shadow Contacts and Extremes: Total Solar Eclipse of 1977 Oct 12

Contacts of Umbral Shadow with Earth
Contact Event Contact Time
TD
Time
UT1
Latitude Longitude
First External ContactU118:48:59.618:48:11.238°54.2'N170°43.4'E
First Internal ContactU218:49:37.318:48:49.039°01.9'N170°35.6'E
Last Internal ContactU322:05:23.422:04:35.006°01.7'N065°21.2'W
Last External ContactU422:06:05.622:05:17.305°53.0'N065°30.6'W
Extreme Northern and Southern Path Limits of Umbra
Contact Event Contact Time
TD
Time
UT1
Latitude Longitude
North Extreme Path Limit 1N118:49:24.818:48:36.439°08.0'N170°40.1'E
South Extreme Path Limit 1S118:49:12.218:48:23.938°48.0'N170°38.8'E
North Extreme Path Limit 2N222:05:37.422:04:49.106°08.7'N065°25.6'W
South Extreme Path Limit 2S222:05:51.422:05:03.105°46.0'N065°26.1'W

Explanation of Umbral Shadow Contacts and Extremes Tables

Central Line Extremes and Duration: Total Solar Eclipse of 1977 Oct 12

Extreme Limits of the Central Line
Contact Event Contact Time
TD
Time
UT1
Latitude Longitude
Extreme Central Line Limit 1C118:49:18.418:48:30.138°58.0'N170°39.5'E
Extreme Central Line Limit 2C222:05:44.522:04:56.205°57.3'N065°25.9'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 Eclipse20:27:27.320:26:38.914°07.5'N123°46.2'W 67.3° 196.9° 98.6 km02m37.28s
Greatest Duration20:30:55.420:30:07.113°34.8'N122°35.6'W 67.3° 201.8° 99.0 km02m37.40s

Explanation of Greatest Eclipse and Greatest Duration

Polynomial Besselian Elements: Total Solar Eclipse of 1977 Oct 12

Polynomial Besselian Elements
1977 Oct 12 at 20:00:00.0 TD (=t0)
n x y d l1 l2 μ
0 -0.13762 0.44133 -7.5856 0.54333 -0.00282 123.3902
1 0.54020 -0.16101 -0.0152 -0.00009 -0.00009 15.0039
2 0.00003 0.00002 0.0000 -0.00001 -0.00001 -0.0000
3 -0.00001 0.00000 - - - -
Tan ƒ1 0.0046861
Tan ƒ2 0.0046627

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 Polynomial Besselian Elements

Links for the Total Solar Eclipse of 1977 Oct 12

Links to Additional Solar Eclipse Information

Eclipse Predictions

Predictions for the Total Solar Eclipse of 1977 Oct 12 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 48.3 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.