Solar eclipse of July 11, 1991

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Solar eclipse of July 11, 1991
Eclipse CR 1991 a zoom.jpg
Totality from Playas del Coco, Costa Rica
Type of eclipse
Maximum eclipse
Duration413 sec (6 m 53 s)
Coordinates22°00′N 105°12′W / 22°N 105.2°W / 22; -105.2
Max. width of band258 km (160 mi)
Times (UTC)
(P1) Partial begin16:28:46
(U1) Total begin17:21:41
Greatest eclipse19:07:01
(U4) Total end20:50:28
(P4) Partial end21:43:24
Saros136 (36 of 71)
Catalog # (SE5000)9489

A total solar eclipse occurred on Thursday, July 11, 1991. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of the Sun for a viewer on Earth. A total solar eclipse occurs when the Moon's apparent diameter is larger than the Sun's, blocking all direct sunlight, turning day into darkness. Totality occurs in a narrow path across Earth's surface, with the partial solar eclipse visible over a surrounding region thousands of kilometres wide. Totality began over the Pacific Ocean and Hawaii moving across Mexico, down through Central America and across South America ending over Brazil. It lasted for 6 minutes and 53 seconds at the point of maximum eclipse. There will not be a longer total eclipse until June 13, 2132.

This eclipse was the most central total eclipse in 800 years, with a gamma of -.0041. There will not be a more central eclipse for another 800 years. Its magnitude was also greater than any eclipse since the 6th century.


Related eclipses[edit]

Solar eclipses 1990-1992[edit]

This eclipse is a member of a semester series. An eclipse in a semester series of solar eclipses repeats approximately every 177 days and 4 hours (a semester) at alternating nodes of the Moon's orbit.[1]

This eclipse is the center of seven central solar eclipses.

Saros 136[edit]

Solar Saros 136, repeating every 18 years, 11 days, contains 71 events. The series started with partial solar eclipse on June 14, 1360, and reached a first annular eclipse on September 8, 1504. It was a hybrid event from November 22, 1612, through January 17, 1703, and total eclipses from January 27, 1721 through May 13, 2496. The series ends at member 71 as a partial eclipse on July 30, 2622, with the entire series lasting 1262 years. The longest eclipse occurred on June 20, 1955, with a maximum duration of totality at 7 minutes, 7.74 seconds. All eclipses in this series occurs at the Moon’s descending node.[2]

Inex series[edit]

This eclipse is a part of the long period inex cycle, repeating at alternating nodes, every 358 synodic months (≈ 10,571.95 days, or 29 years minus 20 days). Their appearance and longitude are irregular due to a lack of synchronization with the anomalistic month (period of perigee). However, groupings of 3 inex cycles (≈ 87 years minus 2 months) comes close (≈ 1,151.02 anomalistic months), so eclipses are similar in these groupings. In the 18th century:

• Solar Saros 127: Total Solar Eclipse of 1731 Jan 08

• Solar Saros 128: Annular Solar Eclipse of 1759 Dec 19

• Solar Saros 129: Annular Solar Eclipse of 1788 Nov 27

In the 23rd century:

• Solar Saros 144: Annular Solar Eclipse of 2223 Feb 01

• Solar Saros 145: Total Solar Eclipse of 2252 Jan 12

• Solar Saros 146: Annular Solar Eclipse of 2280 Dec 22

Tritos series[edit]

This eclipse is a part of a tritos cycle, repeating at alternating nodes every 135 synodic months (≈ 3986.63 days, or 11 years minus 1 month). Their appearance and longitude are irregular due to a lack of synchronization with the anomalistic month (period of perigee), but groupings of 3 tritos cycles (≈ 33 years minus 3 months) come close (≈ 434.044 anomalistic months), so eclipses are similar in these groupings.

Metonic series[edit]

The metonic series repeats eclipses every 19 years (6939.69 days), lasting about 5 cycles. Eclipses occur in nearly the same calendar date. In addition, the octon subseries repeats 1/5 of that or every 3.8 years (1387.94 days). All eclipses in this table occur at the Moon's descending node.


  1. ^ van Gent, R.H. "Solar- and Lunar-Eclipse Predictions from Antiquity to the Present". A Catalogue of Eclipse Cycles. Utrecht University. Retrieved 6 October 2018.
  2. ^ SEsaros136 at