223 lunar months equals 6585.3 days (223 ×29.530588), that is, 18 years zero1.3 days. If there are five leap years in this period, it is 18 years zero1. During this period, the relative position of the intersection of the sun, the moon and the yellow and white is constantly changing, and after a Sharo cycle, the intersection of the sun, the moon and the yellow and white almost returns to its original relative position, so there will be a solar eclipse and a lunar eclipse similar to the last one, but the location of the eclipse will change, so I won't elaborate here.
It was also found in the Han Dynasty that solar and lunar eclipses had a period of 135 moons. 135 moons is equal to 3986.6 days, which is about equal to 1 1 young 3 1 day, that is to say, solar and lunar eclipses occur once every 1 1 young 3 1 day. This cycle is recorded in the "Three Calendars" of the Han Dynasty, so it is also called "Three Calendars Cycle".
In addition, people also found that there are other cycles of solar and lunar eclipses. For example, the Newcomb cycle (20 days in 29 years) with a period of 358 moons, the Milton cycle (0/9 years) with a period of 235 moons, etc., but these cycles are very rough, and only the dates of the solar and lunar eclipses can be roughly calculated, but the exact time of the solar and lunar eclipses, the size of the eclipses and the areas where they are seen can not be determined. The exact time of solar and lunar eclipses and the situation of eclipses need to be calculated strictly, which belongs to the research scope of "food theory" in almanac astronomy. The Purple Mountain Observatory in China is responsible for the forecast of solar and lunar eclipses.
There are at least two eclipses in a year, and both of them are eclipses.
There may not be an eclipse once a year (e.g. 1980);
There can be at most seven eclipses in a year: five eclipses and two eclipses (for example, 1935), or four eclipses and three eclipses (for example, 19 17 years and 1982).
Generally speaking, the most common situation is that there are four eclipses in a year: two eclipses and two eclipses.
The above situation is only for the whole earth. As for a certain place on the earth, the chances of seeing solar and lunar eclipses in a year are much less.
In addition, from the above figures, the number of solar eclipses in a year is more than the number of eclipses, but in fact people often see more eclipses than eclipses. This is because when the eclipse occurs, people on the half of the earth with their backs to the sun can see it; When the solar eclipse occurs, the shadow cone of the moon only sweeps through a narrow area on the earth, and only people in this area can see the solar eclipse, especially when the total solar eclipse occurs, the scope of the total solar eclipse belt is even smaller, and the width is only two or three hundred kilometers, so only a few people can see it. On average, it takes 200 to 300 years for a place to see a total solar eclipse. Therefore, it is not surprising that many people have never seen a total solar eclipse in their lives. For example, the lunar eclipse that occurred on the night of March 2, 196 1 can be seen in China, the whole of Asia and Europe. On September 22nd, 1968, the total solar eclipse occurred in/kloc-0. In China, only parts of Xinjiang can see the total solar eclipse, and only partial solar eclipse can be seen in Beijing, but nothing can be seen in Shanghai.
The area where the solar eclipse can be seen when the date food is divided into two sub-centers.
200 1.6.2 1 total food 127 1.050 04m57s Southeast America, Africa.
[Total eclipse: Southern Atlantic, Southern Africa, Madagascar]
2001.12.14 annular food132 0.96803m53s n.&; C. America, nw S. America
[Eclipse: Central Pacific Ocean, Costa Rica]
2002.6. 10 Huanshi137 0.996 00 m 23 s e Asia, Australia, WN. America
[Eclipse: Central Pacific Ocean, western Mexico]
2002. 12.04 total food 142 1.024 02m04s Southern Africa, Antarctica, Indonesia, Australia.
[Total food: South Africa, South India, Australia]
May 3, 20031Huanshi147 0.938 03m37s Europe, Asia, NW N.America.
[Annular: Iceland, Greenland]
2003. 1 1.23 total food1521.038 01m57s Australia, New Zealand, Antarctica, South America.
[Total eclipse: Antarctica]
April 200419 Partial eclipse 1 19 0.736-Antarctica, Africa.
2004. 10. 14 partial eclipse 124 0.927-Asia, Hawaii, Alaska
April 8, 2005 Total and Annular Eclipses 129 1.007 00m42s New Zealand, South and Central America.
[Hybrid: South Pacific, Panama, Colombia, Venezuela]
2005. 10.03 Huanshi 134 0.958 04m32s Europe, Africa, South Asia.
[Eclipse: Portugal, Spain, Libya, Sudan, Kenya]
May 29, 2006 Total Food1391.05204M07s Africa, Europe, western Asia.
[Total: c Africa, Turkey, Russia]
September 22, 2006 Huanshi1440.93507M09s.America, Africa, Antartica
[Annular food: Guyana, Suriname, F. Guiana, Atlantic]
March 2007.19 partial149 0.874-Asia, Alaska
September 2007.11partial154 0.749-South America, Antarctica
2008.2.07 Huanshi1210.96502m12s Antarctica, eastern Australia, New Zealand.
[Eclipse: Antarctica]
August 0, 20081total food 126 1.039 02m27s North America, Europe and Asia.
[Total food: Northern Canada, Greenland, Siberia, Mongolia, China]
2009. 1.26 Huanshi 13 1 0.928 07m54s Southern Africa, Antarctica, Southeast Asia, Australia.
[Eclipse: Southern India, Sumatra, Borneo]
July 22, 2009 Total Food 136 1.080 06m39s East Asia, Pacific Ocean, Hawaii.
[Total eclipse: Indian, Nepali, China, Central Pacific]
20 10. 1. 15 annular food1410.9191m08s Africa, Asia.
[Eclipse: Central Africa, Indian, Malymar, China]
20 10.7. 1 1 total food 146 1.058 05m20s South America
[Total eclipse: southern Pacific, easterris., Chile, Argentina]