Where is the city with no shadow on the telephone pole twice a year?

It is in the city south of the Tropic of Cancer that the sun shines vertically on the ground twice a year.

Due to the direct sunlight, there is a phenomenon of vertical pole without shadow.

On the day of the summer solstice solar term, the sun is almost directly on the Tropic of Cancer, which is the highest latitude that direct sunlight can reach in the northern hemisphere in a year. At this time, the days are the longest and the nights are the shortest in the northern hemisphere.

In March, the equatorial direct sunlight in the northern hemisphere began to move northward; In June, on the tropic of cancer in the northern hemisphere; It began to move south of the equator in September; In June, in the southern hemisphere, on the tropic of cancer.

At noon from summer solstice, this is absolutely (almost) direct. In the tropic of cancer, when the sun takes a vertical object, you will find that the shadow of a person or thing on the ground will fall vertically below the person or thing itself, which is the phenomenon of "standing without a shadow".

Extended data:

The direct point of the sun moves westward every hour, passing through longitude 15 degrees every hour. In the calculation of geography problems, we can roughly take the latitude of moving 0.25 degrees every day.

On the summer solstice, the direct point of the sun is on the tropic of cancer, and then it moves south until it reaches the equator on September 23 (autumnal equinox). At this time, there will be a phenomenon of "standing without a shadow".

China has six famous signs of the Tropic of Cancer, from east to west: Chiayi, Taiwan Province Province; Shantou, Conghua and Fengkai, Guangdong; Guiping, Guangxi; Yunnan mojiang. There is a "peephole" on the sign of the Tropic of Cancer in Chinese mainland.

China is the country with the largest number of tropic of cancer in the world, and Guangdong is the province with the largest number of tropic of cancer in Chinese mainland.

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