A total solar eclipse occurred at the Moon's descending node of orbit on Thursday, July 11, 1991, with a magnitude of 1.08. 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. Occurring about 8 hours after perigee (on July 11, 1991, at 11:00 UTC), the Moon's apparent diameter was larger.
The eclipse 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. This was the largest total solar eclipse of Solar Saros series 136. This eclipse was the most central total eclipse in 800 years, with a gamma of −0.00412. There will not be a more central eclipse for another 800 years. Its magnitude was also greater than any eclipse since the 6th century.
Totality began over the Pacific Ocean and Hawaii, moving across Mexico, down through the Central American countries of Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica and Panama, across Colombia and ending over Brazil. A partial eclipse was visible for parts of southern Canada, the United States, Mexico, Central America, the Caribbean, and South America.
Observations
An observation team funded by the National Natural Science Foundation of China made near-infrared spectroscopic observations in the southern suburbs of La Paz, Baja California Sur, Mexico. Weather was clear on the eclipse day in La Paz. The team captured dozens of frames of the slitless spectrum of the upper layer of photosphere and chromosphere, and the slit spectrum outside the solar surface. They also captured images of the chromosphere and solar prominences. Among the professional observation teams from various countries to La Paz, six used the new CCD sensors for the first time in solar eclipse observation. Among them, the Chinese and Japanese team used it to observe long-wavelength spectra. A team of 320 people from NASA's Johnson Space Center made observation in Mazatlán, Mexico. The local weather was not ideal in the days before the eclipse, but got slightly better as the eclipse day approached. Some people went to San Blas, Nayarit for better weather conditions. In the end, a hole in the clouds appeared in El Cid in western Mazatlan, through which the corona and prominences was visible. Other observers 1 to 5 miles away were clouded out. In San Blas, the corona and prominences were still visible, even though the clouds became thicker during totality. Scientists from the Royal Observatory of Belgium, the Institute of Geodesy and Geophysics of the Chinese Academy of Sciences, and the Institute of Geophysics of the National Autonomous University of Mexico made observations in Mexico City to study the change in gravity during a total solar eclipse.
Alleged ancient Maya prediction The American ethnographer and anthropologist Victoria Bricker and her late husband and colleague Harvey Bricker, claim in their book "Astronomy in the Maya Codices" that by decoding pre-Columbian glyphs from the four Maya codices they discovered that pre-16th century Maya astronomers predicted the solar eclipse of July 11, 1991. In their 2011 volume, the husband-wife Brickers team explain how they translated the dates from the Maya calendar, then used modern scientific knowledge of planetary orbits to line up the data from the Maya prediction with the Gregorian calendar. Reviewers disputed the claim in 2014, concluding that, "loose hieroglyphic readings and accommodating pattern matching occurs throughout the book."
Eclipse timing Places experiencing total eclipse Solar Eclipse of July 11, 1991(Local Times)Country or territory City or placeStart of partial eclipseStart of total eclipseMaximum eclipseEnd of total eclipseEnd of partial eclipseDuration of totality (min:s)Duration of eclipse (hr:min)Maximum magnitude Hilo 06:30:41 07:28:25 07:30:27 07:32:30 08:38:10 4:05 2:07 1.0273 Mazatlán 10:32:35 11:58:50 12:01:36 12:04:21 13:28:23 5:31 2:56 1.0163 Tepic 10:37:18 12:04:05 12:07:24 12:10:42 13:34:01 6:37 2:57 1.0288 Guadalajara 11:41:50 13:09:13 13:12:20 13:15:26 14:38:17 6:13 2:56 1.0231 Aguascalientes 11:43:41 13:11:43 13:13:25 13:15:06 14:38:22 3:23 2:55 1.0055 León 11:45:49 13:12:56 13:15:53 13:18:49 14:40:40 5:53 2:55 1.0201 Mexico City 11:54:01 13:20:58 13:24:17 13:27:36 14:47:43 6:38 2:54 1.0329 Ecatepec 11:54:08 13:21:08 13:24:19 13:27:29 14:47:39 6:21 2:54 1.0269 Texcoco 11:54:36 13:21:36 13:24:46 13:27:55 14:48:00 6:19 2:53 1.0264 Cuernavaca 11:54:16 13:21:29 13:24:47 13:28:05 14:48:21 6:36 2:54 1.0313 Puebla 11:56:53 13:23:47 13:27:00 13:30:13 14:49:50 6:26 2:53 1.0291 Oaxaca 12:03:02 13:30:31 13:33:15 13:35:59 14:55:10 5:28 2:52 1.0175 Tuxtla Gutiérrez 12:13:05 13:39:38 13:41:30 13:43:22 15:00:44 3:44 2:48 1.0076 Quetzaltenango 13:19:39 14:44:25 14:47:34 14:50:42 16:05:40 6:17 2:46 1.0369 Escuintla 13:22:24 14:46:45 14:49:50 14:52:54 16:07:18 6:09 2:45 1.0334 Guatemala City 13:22:38 14:47:09 14:49:51 14:52:32 16:07:07 5:23 2:44 1.0199 Santa Ana 12:26:00 13:50:01 13:52:37 13:55:13 15:09:08 5:12 2:43 1.0185 San Salvador 12:27:20 13:51:04 13:53:43 13:56:21 15:09:57 5:17 2:43 1.0198 San Vicente 12:28:27 13:52:16 13:54:33 13:56:49 15:10:27 4:33 2:42 1.0134 San Miguel 12:30:13 13:54:16 13:55:52 13:57:28 15:11:19 3:12 2:41 1.0062 León 12:34:54 13:57:44 13:59:40 14:01:35 15:14:04 3:51 2:39 1.0096 Managua 12:36:50 13:59:40 14:01:07 14:02:34 15:15:03 2:54 2:38 1.0053 Masaya 12:37:28 14:00:00 14:01:38 14:03:16 15:15:26 3:16 2:38 1.0069 Liberia 12:40:57 14:01:48 14:04:39 14:07:28 15:17:51 5:40 2:37 1.0306 Alajuela 12:44:42 14:04:48 14:07:25 14:10:00 15:19:40 5:12 2:35 1.0231 San José 12:45:07 14:05:08 14:07:44 14:10:18 15:19:53 5:10 2:35 1.0227 Limón 12:47:28 14:09:10 14:09:12 14:09:15 15:20:37 0:05 2:33 1.0003 David 13:51:00 15:09:29 15:12:12 15:14:54 16:23:02 5:25 2:32 1.0308 Santiago de Veraguas 13:54:37 15:12:43 15:14:37 15:16:31 16:24:25 3:48 2:30 1.0111 Cali 14:09:42 15:23:20 15:25:40 15:27:58 16:31:59 4:38 2:22 1.0234References:
Places experiencing partial eclipse Solar Eclipse of July 11, 1991(Local Times)Country or territory City or placeStart of partial eclipseMaximum eclipseEnd of partial eclipseDuration of eclipse (hr:min)Maximum coverage Honolulu 06:31:28 07:29:45 08:35:21 2:04 96.33% Los Angeles 10:12:12 11:27:55 12:47:22 2:35 69.13% Hermosillo 10:22:06 11:45:29 13:09:54 2:48 85.16% Acapulco 11:54:51 13:26:08 14:50:12 2:55 96.27% Veracruz 12:02:16 13:31:25 14:52:41 2:50 99.46% Cancún 12:25:39 13:46:30 14:59:02 2:33 72.61% Belmopan 12:24:05 13:49:06 15:04:44 2:41 90.73% Havana 14:36:24 15:50:35 16:57:25 2:21 55.97% Tegucigalpa 12:31:54 13:56:39 15:11:20 2:39 97.52% George Town 13:41:30 14:57:57 16:06:03 2:25 66.19% Matagalpa 12:36:38 14:00:32 15:14:13 2:38 98.26% Kingston 13:53:54 15:06:00 16:10:11 2:16 59.76% Port-au-Prince 15:04:04 16:10:13 17:09:32 2:05 48.22% Santo Domingo 15:09:34 16:12:44 17:09:35 2:00 43.46% Panama City 13:56:35 15:15:19 16:24:08 2:28 96.12% Oranjestad 15:12:52 16:20:46 17:21:08 2:08 61.79% Willemstad 15:15:20 16:22:16 17:21:50 2:07 60.68% Caracas 15:20:14 16:25:53 17:24:23 2:04 61.35% Bogotá 14:12:37 15:26:46 16:31:44 2:19 97.62% Quito 14:11:27 15:27:27 16:33:47 2:22 86.91% Port of Spain 15:29:24 16:29:10 17:23:00 1:54 49.64% São Paulo 16:56:43 17:31:46 17:35:10 (sunset) 0:38 45.91% Georgetown 15:35:54 16:34:53 17:28:05 1:52 55.24% Iquitos 14:24:14 15:35:44 16:38:33 2:14 86.92% Paramaribo 16:40:03 17:36:52 18:28:21 1:48 52.79% Lima 14:32:43 15:38:16 16:36:32 2:04 48.89% Cayenne 16:43:28 17:38:21 18:28:19 1:45 50.57% Riberalta 15:40:19 16:44:59 17:42:40 2:02 76.31% La Paz 15:45:25 16:46:03 17:40:35 1:55 52.12% Brasília 16:52:55 17:47:49 17:54:20 (sunset) 1:01 90.97%References:
Gallery
In popular culture The 1991 eclipse appears in the music video for Cosas del Amor, a duet by Vikki Carr and Ana Gabriel.
Eclipse details Shown below are two tables displaying details about this particular solar eclipse. The first table outlines times at which the Moon's penumbra or umbra attains the specific parameter, and the second table describes various other parameters pertaining to this eclipse.
+July 11, 1991 Solar Eclipse Times Event Time (UTC) First Penumbral External Contact 1991 July 11 at 16:29:42.3 UTC First Umbral External Contact 1991 July 11 at 17:22:36.8 UTC First Central Line 1991 July 11 at 17:24:13.8 UTC First Umbral Internal Contact 1991 July 11 at 17:25:50.7 UTC First Penumbral Internal Contact 1991 July 11 at 18:18:45.5 UTC Greatest Duration 1991 July 11 at 19:01:51.6 UTC Greatest Eclipse 1991 July 11 at 19:07:00.8 UTC Ecliptic Conjunction 1991 July 11 at 19:07:03.3 UTC Equatorial Conjunction 1991 July 11 at 19:07:07.0 UTC Last Penumbral Internal Contact 1991 July 11 at 19:55:15.7 UTC Last Umbral Internal Contact 1991 July 11 at 20:48:11.3 UTC Last Central Line 1991 July 11 at 20:49:47.8 UTC Last Umbral External Contact 1991 July 11 at 20:51:24.3 UTC Last Penumbral External Contact 1991 July 11 at 21:44:20.2 UTC
+July 11, 1991 Solar Eclipse Parameters Parameter Value Eclipse Magnitude 1.07997 Eclipse Obscuration 1.16633 Gamma −0.00412 Sun Right Ascension 07h22m12.8s Sun Declination +22°05'48.5" Sun Semi-Diameter 15'43.9" Sun Equatorial Horizontal Parallax 08.7" Moon Right Ascension 07h22m12.5s Moon Declination +22°05'33.9" Moon Semi-Diameter 16'42.1" Moon Equatorial Horizontal Parallax 1°01'17.7" ΔT 57.9 s
Eclipse season
This eclipse is part of an eclipse season, a period, roughly every six months, when eclipses occur. Only two (or occasionally three) eclipse seasons occur each year, and each season lasts about 35 days and repeats just short of six months (173 days) later; thus two full eclipse seasons always occur each year. Either two or three eclipses happen each eclipse season. In the sequence below, each eclipse is separated by a fortnight. The first and last eclipse in this sequence is separated by one synodic month.
+ Eclipse season of June–July 1991 June 27Ascending node (full moon) July 11Descending node (new moon) July 26Ascending node (full moon) Penumbral lunar eclipseLunar Saros 110 Total solar eclipseSolar Saros 136 Penumbral lunar eclipseLunar Saros 148
Related eclipses Eclipses in 1991 An annular solar eclipse on January 15. A penumbral lunar eclipse on January 30. A penumbral lunar eclipse on June 27. A total solar eclipse on July 11. A penumbral lunar eclipse on July 26. A partial lunar eclipse on December 21.
Metonic Preceded by: Solar eclipse of September 23, 1987 Followed by: Solar eclipse of April 29, 1995
Tzolkinex Preceded by: Solar eclipse of May 30, 1984 Followed by: Solar eclipse of August 22, 1998
Half-Saros Preceded by: Lunar eclipse of July 6, 1982 Followed by: Lunar eclipse of July 16, 2000
Tritos Preceded by: Solar eclipse of August 10, 1980 Followed by: Solar eclipse of June 10, 2002
Solar Saros 136 Preceded by: Solar eclipse of June 30, 1973 Followed by: Solar eclipse of July 22, 2009
Inex Preceded by: Solar eclipse of July 31, 1962 Followed by: Solar eclipse of June 21, 2020
Triad Preceded by: Solar eclipse of September 9, 1904 Followed by: Solar eclipse of May 11, 2078
Solar eclipses of 1990–1992
Saros 136
Metonic series
Tritos series
Inex series
Notes
References
NASA graphics Google interactive map of the eclipse from NASA NASA Besselian Elements - Total Solar Eclipse of July 11, 1991 Observer's handbook 1991, Editor Roy L. Bishop, The Royal Astronomical Society of Canada (p. 101)
Photos: Russian scientist observed eclipse Russia expedition Baja California, La Paz. Prof. Druckmüller's eclipse photography site