Solar Eclipse Prime Page

Annular Solar Eclipse of -1977 Apr 11 (1978 Apr 11 BCE)

Fred Espenak

Introduction

eclipse map

The Annular Solar Eclipse of -1977 Apr 11 (1978 Apr 11 BCE) 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 -1977 Apr 11 at 00:16:37 TD (11:32:13 UT1). This is 6.2 days before the Moon reaches apogee. During the eclipse, the Sun is in the constellation Taurus. The synodic month in which the eclipse takes place has a Brown Lunation Number of -48233.

The eclipse belongs to Saros 7 and is number 35 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 annular solar eclipse of -1977 Apr 11 is preceded two weeks earlier by a penumbral lunar eclipse on -1977 Mar 28, and it is followed two weeks later by a penumbral lunar eclipse on -1977 Apr 26.

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 45863.4 seconds for this eclipse. The uncertainty in ΔT is 3634.7 seconds corresponding to a standard error in longitude of the eclipse path of ± 15.19°.

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 -1977 Apr 11 .

Eclipse Data: Annular Solar Eclipse of -1977 Apr 11

Eclipse Characteristics
Parameter Value
Eclipse Magnitude 0.99270
Eclipse Obscuration 0.98546
Gamma-0.01364
Conjunction Times
Event Calendar Date and Time Julian Date
Greatest Eclipse -1977 Apr 11 at 00:16:36.7 TD (11:32:13.3 UT1) 999057.980709
Ecliptic Conjunction -1977 Apr 11 at 00:16:27.3 TD (11:32:04.0 UT1) 999057.980601
Equatorial Conjunction -1977 Apr 11 at 00:15:44.4 TD (11:31:21.0 UT1) 999057.980104
Geocentric Coordinates of Sun and Moon
-1977 Apr 11 at 00:16:36.7 TD (11:32:13.3 UT1)
Coordinate Sun Moon
Right Ascension00h09m27.5s00h09m29.0s
Declination+01°03'02.6"+01°02'22.4"
Semi-Diameter 15'45.2" 15'23.7"
Eq. Hor. Parallax 08.7" 0°56'29.9"
Geocentric Libration of Moon
Angle Value
l 5.6°
b -0.1°
c -22.3°
Prediction Paramaters
Paramater Value
Ephemerides JPL DE406
ΔT 45863.4 s
k (penumbra) 0.2725076
k (umbra) 0.2722810
Saros Series 7 (35/72)

Explanation of Solar Eclipse Data Tables

Penumbral Shadow Contacts and Extremes: Annular Solar Eclipse of -1977 Apr 11

Contacts of Penumbral Shadow with Earth
Contact Event Contact Time
TD		 Time
UT1		 Latitude Longitude
First External ContactP121:22:03.308:37:39.930°16.0'S037°31.1'W
First Internal ContactP223:26:24.610:42:01.231°31.0'S068°34.2'W
Last Internal ContactP301:06:48.812:22:25.428°00.1'N086°15.0'E
Last External ContactP403:11:16.714:26:53.329°15.1'N055°10.2'E
Extreme Northern and Southern Path Limits of Penumbra
Contact Event Contact Time
TD		 Time
UT1		 Latitude Longitude
North Extreme Path Limit 1N122:42:10.709:57:47.303°01.9'N058°14.7'W
South Extreme Path Limit 1S122:43:45.009:59:21.764°19.5'S056°23.6'W
North Extreme Path Limit 2N201:50:36.513:06:13.162°28.1'N076°47.9'E
South Extreme Path Limit 2S201:49:57.113:05:33.704°56.7'S074°46.9'E

Explanation of Penumbral Shadow Contacts and Extremes Tables

Umbral Shadow Contacts and Extremes: Annular Solar Eclipse of -1977 Apr 11

Contacts of Umbral Shadow with Earth
Contact Event Contact Time
TD		 Time
UT1		 Latitude Longitude
First External ContactU122:23:29.809:39:06.530°32.4'S052°52.1'W
First Internal ContactU222:24:55.509:40:32.130°33.0'S053°13.6'W
Last Internal ContactU302:08:16.313:23:52.928°58.1'N070°54.6'E
Last External ContactU402:09:47.613:25:24.328°58.7'N070°31.8'E
Extreme Northern and Southern Path Limits of Umbra
Contact Event Contact Time
TD		 Time
UT1		 Latitude Longitude
North Extreme Path Limit 1N122:24:12.409:39:49.030°10.8'S053°03.3'W
South Extreme Path Limit 1S122:24:13.109:39:49.730°54.6'S053°02.4'W
North Extreme Path Limit 2N202:09:02.013:24:38.629°21.7'N070°43.8'E
South Extreme Path Limit 2S202:09:01.913:24:38.528°35.0'N070°42.7'E

Explanation of Umbral Shadow Contacts and Extremes Tables

Central Line Extremes and Duration: Annular Solar Eclipse of -1977 Apr 11

Extreme Limits of the Central Line
Contact Event Contact Time
TD		 Time
UT1		 Latitude Longitude
Extreme Central Line Limit 1C122:24:12.709:39:49.330°32.7'S053°02.9'W
Extreme Central Line Limit 2C202:09:02.013:24:38.628°58.4'N070°43.2'E

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 Eclipse00:16:36.711:32:13.300°22.4'N177°00.3'E 89.2° 330.3° 25.6 km00m43.55s
Greatest Duration02:09:02.013:24:38.628°58.4'N070°43.2'E 0.0° 271.2° 86.3 km01m31.32s

Explanation of Greatest Eclipse and Greatest Duration

Polynomial Besselian Elements: Annular Solar Eclipse of -1977 Apr 11

Polynomial Besselian Elements
-1977 Apr 11 at 00:00:00.0 TD (=t0)
n x y d l1 l2 μ
0 -0.12164 -0.08479 1.0465 0.55275 0.00656 179.2275
1 0.46370 0.26341 0.0155 0.00012 0.00012 15.0057
2 -0.00001 -0.00001 -0.0000 -0.00001 -0.00001 0.0000
3 -0.00001 -0.00000 - - - -
Tan ƒ1 0.0046059
Tan ƒ2 0.0045830

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 = 0.000

Explanation of Polynomial Besselian Elements

Links for the Annular Solar Eclipse of -1977 Apr 11 (1978 Apr 11 BCE)

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 Annular Solar Eclipse of -1977 Apr 11 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 45863.4 seconds for this eclipse. The uncertainty in ΔT is 3634.7 seconds corresponding to a standard error in longitude of the eclipse path of ± 15.19°.

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.