How often does a total solar eclipse occur on average

Experts from the National Astronomical Observatories of China explained that more than 300 years is the time when a total solar eclipse was observed again at a fixed location. Specifically, when a total solar eclipse occurs, it will project a total solar eclipse shadow band on the Earth, which is very narrow and only about 200 kilometers wide. This time, Hangzhou is located within the shadow zone of the total solar eclipse, and the next time Hangzhou enters the shadow zone of the total solar eclipse, it will not be until 2309, 300 years later.

Generally speaking, it takes an average of 370 years for a point on Earth to enter a total solar eclipse shadow zone.

As for saying that tomorrow's total solar eclipse will occur once in 500 years, this statement is based on the history of total solar eclipse observation in China. According to records, in the 495 years from 1814 to 2309, tomorrow's total solar eclipse will be the longest total solar eclipse in China, lasting more than 6 minutes. It can be said that such a "high-quality, long-term" total solar eclipse did not occur in the first 200 years, and it will not happen in the next 300 years.

Therefore, it is indeed rare to see it in 500 years.

In fact, there can be up to 5 solar eclipses per year around the world. If it doesn't fall once out of 5, then it must be a partial solar eclipse every time. In addition to this, there are at least two solar eclipses per year on Earth.

A total solar eclipse occurs about every year and a half. And some people spend their entire lives without being able to see a single eclipse at their doorstep.

On average, a total solar eclipse occurs once a year around the world. For the same location, total solar eclipses generally occur with a frequency of about 300 years. As for total lunar eclipses, according to statistics within the "Saro Cycle", there are about 28 lunar eclipses (about 43 solar eclipses) in a cycle of about 6,585 days (a little more than 18 years), of which 12 to 13 are total lunar eclipses.

To put it simply, a total lunar eclipse occurs about once every year and a half.

It should be noted that each lunar eclipse occurs when it is only visible to people halfway around the world (night hemisphere), so it takes an average of three years to see a total lunar eclipse in the same area.

In terms of the number of occurrences around the world, there are actually more solar eclipses than lunar eclipses in a year. From Earth, the orbits of the Sun and Moon "intersect" every six months, and the period of time when a solar eclipse may occur (eclipse season) is longer than the period of time when a lunar eclipse occurs (lunar eclipse season).

A total solar eclipse is an average of once and a half a year. A typical total eclipse zone is about 10,000 kilometers long and 200 kilometers wide, so when a total solar eclipse occurs, it can only be observed over a small area on Earth. If a person stays in one place, it will take an average of about 400 years to see a total solar eclipse, and to enjoy such a spectacular celestial event, it will take a long journey under most conditions.

Causes of solar eclipses.

The reason for a solar eclipse is that when the moon orbits the earth, when the moon happens to be between the sun and the earth, and the sun, moon and earth are almost in the same straight line, the moon obscures the sunlight and the moon's shadow falls on the earth, so a solar eclipse occurs.

Therefore, the time of the solar eclipse must be around the first day of the lunar calendar; But because between the white path (the Moon's orbit around the Earth) and the ecliptic (the Earth's orbit around the Sun), there is an average of 5°9'Therefore, not every new day will occur a solar eclipse, but must occur when the moon is within a degree of the intersection of the ecliptic and the white way, and this range is called the solar eclipse limit.

First of all, the total solar eclipse is a common astronomical phenomenon that occurs twice every 3 years. The total solar eclipse zone is no more than 300 kilometers wide on Earth and only a few dozen kilometers at its narrowest.

Based on the historically valid records of total solar eclipses, for a city or a region, it can only be observed once every 370 years on average, hence the saying "once in 370 years".

However, the statement that "it occurs once in 370 years" is also not rigorous enough. Because a total solar eclipse will be affected by the orbit of the Sun and Moon, the rotation of the Earth, and other factors. It's not that a total solar eclipse happened somewhere today, and it will definitely reappear in the same place 370 years from now.

1. There are up to 5 solar eclipses per year, and if there are 5 times, then they must be partial eclipses. There are at least 2 solar eclipses per year on Earth. Only partial solar eclipses can be seen in the Arctic and Antarctic regions. A total solar eclipse occurs about once every 1 1/2 years.

2. An eclipse season of a solar eclipse is 36 days, which is longer than the average length of a synodic month. Therefore, there must be one eclipse during the eclipse season of an eclipse, and two eclipses may occur. There are two eclipse seasons in a year, so there are at least two eclipses in a year, and possibly four (if each eclipse season includes two new days).

Total solar eclipses are very rare, and if a person stays in one place and does not move, they will only see a total solar eclipse once in about 400 years on average.

But on a national scale, or on a global scale, the probability of a total solar eclipse is not low. NASA plotted the trajectory of the total solar eclipse zone (blue area) from 1000 to 2000 AD on a map of the world. Over the past 1,000 years, a total solar eclipse has been observed almost worldwide.

Zooming out the map to China, the day of the last total solar eclipse is not far off. On July 22, 2009, a six-and-a-half-minute total solar eclipse was observed in the Yangtze River basin in China, the longest since July 11, 1991, and the record will remain until 2132. Going back further, the total solar eclipse belt on August 1, 2008 also passed through northern China and ended in Henan Province at sunset.