Where is the direction of sunrise and sunset?

There are two scenarios:

1. In the Northern Hemisphere, the Sun rises due north and sets due north at the latitude corresponding to the lowest latitude where the polar day appears.

The lowest latitude at which the polar day occurs is not a fixed value, this latitude varies from day to day, but the sum of this latitude is more than the latitude of the point of direct light.

Every year on the spring equinox (March 21) and autumn equinox (September 32), the sun rises due east at 6 a.m. local time and sets due west at 6 p.m. local time. In other words, due east corresponds to 6 o'clock local time, and due west direction corresponds to 18 o'clock local time.

Further, the direction of due north corresponds to the direction of 0:00 local time, and the direction of due south corresponds to the direction of 12:00 local time.

From March 22 to September 22, it is the summer half of the Northern Hemisphere, and the days are long and the nights are short in various parts of the Northern Hemisphere, with sunrise before 6 o'clock local time and sunset after 6 p.m. local time. As a result, the Sun rises in the northeast (between 0 and 6 o'clock) and sets in the northwest (between 18 and 0 o'clock).

During this period, the higher the latitude of the Northern Hemisphere, the longer the days and the shorter the nights, the more northerly the sunrise and sunset azimuth, and at the lowest latitude where the polar day occurs, the sunrise and sunset azimuth are the most northerly, that is, due north sunrise and due north sunset.

2. South Pole, on September 23 of each year, at the end of the long polar day, the sun rises due north (because the south pole is north on all sides), and begins a six-month (September 23 to March 21 of the following year), and on March 21 of the following year, at the end of the polar day, the sun sets from the north direction, and begins the polar night period of half a year (March 21 to September 23). Cycle.

During non-polar night hours at the South Pole, the Sun rises due north. (Because at the South Pole all directions are due north.) ）

At the South Pole, you can see the sun rise because in any direction of the South Pole is north.

There are two scenarios:

First: the North Pole, not the South Pole as upstairs, because the direction of the sun and the direction of the shadow of the sun are opposite, standing at the north pole, the shadow of the sun is always facing south, so the sun rises from due north.

Second: at the latitude north of the Arctic Circle, for example, if the sun is directly 20°N on a given day, then the polar day will occur north of 70°N (90 20), and at 70°N the direction of sunrise is due north, because the shadow there faces south.

It should be the sun that came first, and the direction in which the sun rose was called the east.

When the direct point of the sun is in the Northern Hemisphere, except for the polar day and night regions, all points in the world have sunrise northeast and sunset northwest.

When the direct point of the sun is in the southern hemisphere, all points in the world except for the polar day and night regions have sunrise southeast and sunset southwest.

When the direct point of the sun is at the equator, the sunrise is due east and the sunset is due west at all points around the world.

How did you get this rule?

To understand this question, we must first understand two questions, the meaning of the dmorning and dusk line. The morning and dusk line is the dividing line between day and night, from night to day needs to pass through the morning line, from day to night needs to pass through the dusk line, so the morning line represents the sunrise, and the dusk line represents the sunset.

All the points on the earth that are rising at sunrise are on the morning line, and all the points that are setting at sunset are on the evening line, so if we want to study the sunrise or sunset orientation of any place, we need to observe it on the morning line. Sunset should be combined with a dusk line study. Determination of the orientation of the earth.

The meridian line represents due south and north, and the latitude line represents due east and west.

The two images below represent the light maps centered on the morning and dusk lines when the sun is directly shining in the northern hemisphere, with the solid red line representing the sun's rays, the pink solid line representing the east-west direction, the blue solid line representing the north-south direction, and the green shade representing the night.

To sum up, when the direct point of the sun is in the Northern Hemisphere, except for the polar day and night region, all points in the world have sunrise in the northeast and sunset in the northwest.

In the same way, when the direct point of the sun is in the southern hemisphere, the sunrise is southeast and sunset is southwest at all points in the world, except for the polar day and night regions.

When the direct point of the sun is at the equator, the sunrise is due east and the sunset is due west at all points around the world.

The direction of sunrise is the east.

The equator is the bisector of the northern and southern hemispheres, where day and night are equinoxized all year round, and it is 12 hours. So when the sun shines directly here, the global sunrise and sunset are very special. When the sun shines directly on the equator, that is, on the spring and autumn equinoxes, the sun rises due east and sets due west around the world.

So there are only 2 days in a year when the sun really rises due east and sets due west.

The movement of the point of direct sunlight

The direct point of the sun moves back and forth between 23°26 n and 23°26 s of the earth, and the period of movement is a return year (365 days, 5:48:46 seconds), and the law of movement is as follows:

In the summer half of the year (spring equinox-summer solstice-autumn equinox), the direct point of the sun starts from the equator and first moves north to the Tropic of Capricorn.

Head south back to the equator.

In the winter half of the year (autumnal equinox-winter solstice-spring equinox), the sun's direct defeat starts from the equator and first moves south to the Tropic of Capricorn.

Head north back to the equator.

Sunrise direction: northeast sunrise, northwest sunset. However, the time of sunrise changes depending on the season and the latitude of each place.

Traditionally, the winter solstice is believed to be the latest in the Northern Hemisphere, but in fact the latest sunrise is in early January. By the same token, the earliest sunrise is not on the summer solstice, but at the beginning of June.

Sunrise refers to the first rise of the sun over the horizon or the appearance of the sun as first seen. Generally refers to the time when the sun rises slowly over the eastern horizon. Exactly that is defined as the moment when the sun just rises above the horizon, not the entire sun away from the horizon.

In ancient China, the day was divided into 12 hours.

The formation of the sunrise

Because sunlight is refracted by the earth's atmosphere, people can already see the sunrise when the sun has not yet risen above the horizon, which is the illusion of selling at sunrise every day.

Ancient Chinese astronomers recorded a rare astronomical phenomenon called "Tian Zaidan", which means that two sunrises occur in quick succession on the same day. An astronomical spectacle, usually caused by a total solar eclipse between 5 and 7 a.m., the first sunrise darkens again, followed by a second sunrise.

Sunrise in the east.

Sunrise refers to the first rise of the sun over the horizon or the appearance of the sun as first seen. Generally refers to the time when the sun rises slowly over the horizon in the east, but it is indeed defined as the moment when the sun surface just rises above the horizon, rather than the entire sun surface leaving the horizon.

At sunrise, the sunlight is scattered by the dust of the earth's atmosphere, so the sky will be filled with haze, but the sunrise is lighter than the sunset, because the dust in the atmosphere at sunrise is less stuffy than at sunset. The time of sunrise varies depending on the season and the latitude of each place. Traditionally, the winter solstice is believed to be the latest sunrise in the Northern Hemisphere, but in fact the latest sunrise is in early January.

It depends. The direction of sunrise and sunset in the Dongmin Lap Bridge season is according to the sun's rays.

Different directions are caused by different irradiation angles. When the Northern Hemisphere.

In winter, the sun shines directly on the Southern Hemisphere.

The direction of the sunrise is southeast, and the direction of sunset is southwest; When it is winter in the Southern Hemisphere, the Sun shines directly on the Northern Hemisphere, and the direction of the sunrise is northeast and the direction of sunset is northwest. But in life, it is roughly said that the sunrise in the east and the sunset in the west are fierce. <

Subject to the situation of the CIA. In winter, the direction of sunrise and sunset varies depending on the angle of sunlight. When it is winter in the Northern Hemisphere, the Sun shines directly on the Southern Hemisphere, the direction of the sunrise is southeast, and the direction of sunset is southwest; When it is winter in the Southern Hemisphere, the Sun shines directly on the Northern Hemisphere, and the direction of the sunrise is northeast and the direction of sunset is northwest.

But in life, it is roughly said that the sun rises in the east and the sun sets in the west.

In summer, the sun shines directly on the Northern Hemisphere, and the Northern Hemisphere has a summer depolarization day.

Outside of the polar night region, the sun rises northeast and sunset northwest. The sun shines directly on the Southern Hemisphere.

In the summer of the Southern Hemisphere, except for the polar day and polar night regions, the sun rises southeast and sunset southwest.

Summer sun sunrise and sunset direction.

The vernal equinox is the world, except for the poles, where the sun rises in the east and sets in the west. From the spring equinox to the summer solstice, except for the poles, the sun rises in the northeast and sets in the northwest, becoming more and more northerly.

In addition to the poles, the summer solstice is the maximum northward rise and setting direction of the sun in various places, and the North Antarctic Circle rises and sets northward, and the Arctic Circle.

The sun never sets, and the sun does not rise in the Antarctic Circle.

The North Pole is due south, and the South Pole is due north. Polar daytime region: Northern Hemisphere, sunrise and sunset are due north; In the Southern Hemisphere, sunrise and sunset are due south.

Northern Hemisphere Summer Half: Both the Northern and Southern Hemispheres rise northeast and fall northwest; Northern Hemisphere Winter Half-Year: Both the northern and southern hemispheres rise in the southeast and fall in the southwest.

In addition to the north and south poles, the spring and autumn equinoxes rise due east and set due west.

In which hemisphere the sun shines directly, the sunrise and sunset are biased. And the higher the latitude, the more pronounced the deflection. The equator is deflected at the direct latitude at that time, and the polar day region is deflected at 90 degrees.

Affected by the "west-to-east" movement of the earth's rotation direction, the apparent motion of the sun is that it rises in the east and sets in the west. Strictly speaking, it is inaccurate to assume that the sun rises in the east and sets in the west. Due to the presence of the yellow-red angle, the direct point of the sun travels back and forth between the Tropic of Cancer and the Tropic of Capricorn.

The change of the position of the direct point makes the sunrise and sunset directions different on different days in the same place, and the sunrise and sunset directions are also different in different places at the same time, so the sunrise and sunset directions we see in different seasons are not the same.

Rule 1: On the equinox of spring and autumn, the sunrise and sunset directions all over the world rise from the east and set from the west except for the north and south poles.

Rule 2: When the sun shines directly on the Northern Hemisphere, the sun rises from the northeast and sets from the northwest except for the polar day and polar night regions around the world, and the closer the latitude of the direct sun point is to the Tropic of Cancer, the more northerly the sunrise and sunset will be; The higher the latitude, the more northerly the sunrise and sunset.

Rule 3: When the sun shines directly on the southern hemisphere, except for the polar day and polar night regions, the sun rises from the southeast and sets from the southwest, and the closer the latitude of the direct sun point is to the Tropic of Capricorn, the more southerly the sunrise and sunset will be; The higher the latitude, the more southerly the sunrise and sunset.