Solar eclipse of July 11, 1991

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 53.08 seconds at the point of maximum eclipse. There will not be a longer total eclipse until June 13, 2132.

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

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 eclipsesEdit

Solar eclipses 1990–1992Edit

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 semester series contains only 7 eclipses.

This eclipse is the center of seven central solar eclipses.

Saros 136Edit

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 seriesEdit

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 seriesEdit

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.

In the 22nd century:

  • Solar Saros 147: Annular Solar Eclipse of 2111 Aug 04
  • Solar Saros 148: Total Solar Eclipse of 2122 Jul 04
  • Solar Saros 149: Total Solar Eclipse of 2133 Jun 03
  • Solar Saros 150: Annular Solar Eclipse of 2144 May 03
  • Solar Saros 151: Annular Solar Eclipse of 2155 Apr 02
  • Solar Saros 152: Total Solar Eclipse of 2166 Mar 02
  • Solar Saros 153: Annular Solar Eclipse of 2177 Jan 29
  • Solar Saros 154: Annular Solar Eclipse of 2187 Dec 29
  • Solar Saros 155: Total Solar Eclipse of 2198 Nov 28

In the 23rd century:

  • Solar Saros 156: Annular Solar Eclipse of 2209 Oct 29
  • Solar Saros 157: Annular Solar Eclipse of 2220 Sep 27
  • Solar Saros 158: Total Solar Eclipse of 2231 Aug 28
  • Solar Saros 159: Partial Solar Eclipse of 2242 Jul 28
  • Solar Saros 160: Partial Solar Eclipse of 2253 Jun 26
  • Solar Saros 161: Partial Solar Eclipse of 2264 May 26
  • Solar Saros 162: Partial Solar Eclipse of 2275 Apr 26
  • Solar Saros 163: Partial Solar Eclipse of 2286 Mar 25
  • Solar Saros 164: Partial Solar Eclipse of 2297 Feb 22

Metonic seriesEdit

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