To the question What are the days called: March 21, June 22, September 23, December 22? given by the author Ride the best answer is As you know, the Earth revolves in its orbit around the Sun. For us, people on the surface of the Earth, this annual movement of the Earth around the Sun is noticeable in the form of the annual movement of the Sun against the background of stars. As we already know, the path of the Sun among the stars is a great circle of the celestial sphere and is called the ecliptic. This means that the ecliptic is a celestial reflection of the Earth’s orbit, therefore the plane of the Earth’s orbit is also called the ecliptic plane. The Earth's rotation axis is not perpendicular to the ecliptic plane, but deviates from the perpendicular at an angle. Thanks to this, the seasons change on Earth (see Fig. 12). Accordingly, the plane of the earth's equator is inclined at the same angle to the plane of the ecliptic. The line of intersection of the plane of the earth's equator and the plane of the ecliptic retains (if precession is not taken into account) an unchanged position in space. One end of it points to the point of the spring equinox, the other - the point of the autumn equinox. These points are motionless relative to the stars (up to precessional movement!) and together with them participate in the daily rotation.
Near March 21 and September 23, the Earth is positioned relative to the Sun in such a way that the boundary of light and shadow on the Earth's surface passes through the poles. And since every point on the surface of the Earth makes diurnal movement around the earth's axis, then exactly half of the day it will be on the illuminated part of the globe, and the second half - on the shaded part. Thus, on these dates, day is equal to night, and they are called the days of the spring and autumn equinoxes, respectively. At this time, the Earth is located at the intersection of the equator and ecliptic planes, i.e., at the points of the spring and autumn equinoxes, respectively.
Let us highlight two more special points in the Earth’s orbit, which are called solstices, and the dates on which the Earth passes through these points are called solstices.
At the summer solstice point, where the Earth is close to June 22 (summer solstice day), North Pole The Earth's direction is directed towards the Sun, and for most of the day any point in the northern hemisphere is illuminated by the Sun, i.e. on this date the day is the longest of the year.
At the point of the winter solstice, at which the Earth is close to December 22 (winter solstice day), the Earth's north pole is directed away from the Sun, and for most of the day any point in the northern hemisphere is in the shadow, i.e. on this date the night is the longest in the year, and the day is the shortest.
Due to the fact that the calendar year does not coincide in length with the period of the Earth’s revolution around the Sun, the days of the equinoxes and solstices in different years may fall on different days (one day from the above dates). However, in the future, when solving problems, we will neglect this and assume that the days of the equinoxes and solstices always fall on the dates indicated above.
Solstices And equinox- special dates in astronomy. They mark the change of astronomical seasons. During the equinoxes, the Sun is at the celestial equator and therefore evenly illuminates the northern and southern hemispheres of the Earth. On these dates (late March and September) day is equal to night. On the days of the solstices, our daylight reaches the extreme points of its annual path across the sky - in summer it deviates 23.4 degrees north from the celestial equator, in winter - 23.4 degrees south. Therefore, in June, the Sun illuminates the northern hemisphere of the Earth more - and at the moment of the solstice, summer begins here - and at the end of December - the southern hemisphere, and at this time winter begins here (and summer in the southern hemisphere).
So, let's figure it out!
The change of day and night on Earth occurs continuously. But only 2 times a year - their duration is the same at all latitudes and is 12 hours - these are the days of the spring (March 21) and autumn (September 23) equinox). It is on these days that the Sun is at its zenith above the equator, and therefore the territories of the northern and southern hemispheres receive equal amounts of heat.
They also distinguish the shortest night of the year and the longest day of the year. This is the day of the summer solstice. Which, in the northern hemisphere, falls on June 22, and in the southern hemisphere, on December 22. Thus, in the northern hemisphere on June 22, the day is longer than the night at all latitudes, while in the southern hemisphere the day is shorter than the night! At this time, polar day and polar night are observed at the poles! 
At the equator, day is always equal to night! The angle of incidence of the sun's rays and the length of the day change very little. 
The resource clearly demonstrates the structure of the "Magic Dome" training model, based on the geometry of the celestial sphere; shows the main elements of the celestial sphere studied in a school geography course; on specific example introduces the operation of the model and teaches how to enter changeable parameters; includes a simulator that helps memorize the basic elements of the model (celestial sphere) |
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Model with variable parameters. The resource allows, by changing model parameters, to establish relationships between geographical latitude places, the visible movement of the sun above the horizon, the daily rotation and orbital movement of the Earth on the days of the equinoxes and solstices; makes it possible to visualize difficult-to-understand geographies studied in school courses astronomical phenomena and processes and their consequences (change of day and night, change of seasons, etc.) |
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- December 22 Winter sun standing
June 22 summer sun standing the earth faces the sun with its north pole
March 21 and September 23 the sun at noon is at its zenith above the equator - 21st and 23rd equinoxes
- And there was something like solstice day, balance, or something else, I don’t remember
- I don't know about you but I don't know
- Most likely these are the days of the solstice.
- March 21 is the day of the vernal equinox; June 22 - summer solstice; September 23 is the day of the autumnal equinox; December 22 - winter solstice
- solstice
- March 21 and September 23 are the spring and autumn equinoxes. June 22 and December 22 are the summer and winter solstice.
- solstice days
- wrong
- equinox days.
- oooh..
complicated - In my opinion, the days of spring, summer and last solstice, if I’m not mistaken!
- DON'T FUCK THE FUCKING FOOL
- As you know, the Earth revolves in its orbit around the Sun. For us, people on the surface of the Earth, this annual movement of the Earth around the Sun is noticeable in the form of the annual movement of the Sun against the background of stars. As we already know, the path of the Sun among the stars is a great circle of the celestial sphere and is called the ecliptic. This means that the ecliptic is a celestial reflection of the Earth’s orbit, therefore the plane of the Earth’s orbit is also called the ecliptic plane. The Earth's rotation axis is not perpendicular to the ecliptic plane, but deviates from the perpendicular at an angle. Thanks to this, the seasons change on Earth (see Fig. 12). Accordingly, the plane of the earth's equator is inclined at the same angle to the plane of the ecliptic. The line of intersection of the plane of the earth's equator and the plane of the ecliptic retains (if precession is not taken into account) an unchanged position in space. One end of it points to the point of the spring equinox, the other - the point of the autumn equinox. These points are motionless relative to the stars (up to precessional movement!) and together with them participate in the daily rotation.
Near March 21 and September 23, the Earth is positioned relative to the Sun in such a way that the boundary of light and shadow on the Earth's surface passes through the poles. And since each point on the Earth’s surface makes a daily movement around the Earth’s axis, then exactly half of the day it will be on the illuminated part of the globe, and the second half on the shaded part. Thus, on these dates, day is equal to night, and they are called the days of the spring and autumn equinoxes, respectively. At this time, the Earth is located at the intersection of the equator and ecliptic planes, i.e., at the points of the spring and autumn equinoxes, respectively.
Let us highlight two more special points in the Earth’s orbit, which are called solstices, and the dates on which the Earth passes through these points are called solstices.
At the point of the summer solstice, in which the Earth is close to June 22 (summer solstice day), the north pole of the Earth is directed towards the Sun, and for most of the day any point in the northern hemisphere is illuminated by the Sun, i.e. on this date the day is the longest of the year .
At the point of the winter solstice, at which the Earth is close to December 22 (winter solstice day), the Earth's north pole is directed away from the Sun, and for most of the day any point in the northern hemisphere is in the shadow, i.e. on this date the night is the longest in the year, and the day is the shortest.
Due to the fact that the calendar year does not coincide in length with the period of the Earth’s revolution around the Sun, the days of the equinoxes and solstices in different years may fall on different days (one day from the above dates). However, in the future, when solving problems, we will neglect this and assume that the days of the equinoxes and solstices always fall on the dates indicated above.
On December 22, 2011 at 14:30 fraternal time (UTC+9h) the Sun will descend to its maximum in the southern hemisphere of the sky, that is, moving along the ecliptic, it will reach its lowest declination -23° 26.457 minutes. In astronomy, the moment of the winter solstice is taken as the beginning of winter. The astronomical longitude of the Sun at this moment is 90° (located in the constellation Sagittarius). After December 22, the Sun will gradually, at first barely noticeable, begin to increase in height until the summer solstice.
In Bratsk, all week around the winter solstice, the Sun rises above the horizon to a height of 10°. These days, in the northern hemisphere of the Earth, the Sun remains least above the horizon. December 21 and 22 are the most short days per year. From 21 to 22 December is the longest night. In Bratsk, the length of daylight hours on the winter solstice will be 6 hours 52 minutes.
Our sunrise on this day is at 10:45 a.m. and sunset is at 5:37 p.m.
During the winter solstice, the Sun does not rise above a latitude of 66.5 degrees, and the night lasts around the clock. Only twilight at these latitudes indicates that the Sun is somewhere below the horizon in the middle of the twilight segment. At the North Pole of the Earth, not only the Sun is not visible, but also twilight, so the direction to the Sun can only be determined by the constellations (it will be located below the constellation Hercules).
Why is this event called that? The fact is that the sun for several days before and after the winter solstice practically does not change its declination, as if “standing” on the same midday altitude. Solstice or solstice marked folk sign: sun - for summer, winter - for frost. Indeed, from this moment on, snow cover in the modern climate is just beginning to be established, although the Sun is sinking deeper and deeper into the southern hemisphere of the sky.
The shortest days are on December 21 and 22. In the first days after December 22, the day increases, but shifts to a later time according to the clock. People say: “The day grows in the evening.” Why is this happening?
The reason lies in the uneven increase in the direct ascension of the Sun throughout the year. In winter, the Earth is closer to the Sun and its orbital speed is greater. Therefore in winter angular velocity The movement of the Sun along the ecliptic is 3.4% more than average.
22 10:45 14:11 17:37 +10° 32’31” 17:57.3 -23°26’
The winter solstice has occupied an important place in culture since at least the Neolithic period. This is believed to be proven by surviving archaeological sites - such as Stonehenge in England and Newgrange in Ireland. The main axis of both structures points to the point of sunrise (Newgrange) or sunset (Stonehenge) on the winter solstice.
Druids gathered at Stonehenge in England
Photo by Matt Cardy/Getty Images Europe
The solstice has long been celebrated by all peoples and is the basis of many religious holidays, including Christmas and the celebration of the birth of Mithras. People attached symbolic meaning to the fiery holiday with bonfires, candles and fiery snakes. It was believed that such a holiday would help the Sun overcome the border and lengthen the day. The ancient Slavs also celebrated the days of the solstices and equinoxes. These days (two solstices and two equinoxes - Kolyada, Velikden, Kupala and Ovsen - Tausen) served as starting points for farming, construction, and other matters vital to society. These days, in addition to the exact date, also have their own “week” (Rusalia, Carols and others).
In the days around the solstice, the declination of the Sun changes very slowly. In the first seven days after the solstice, the increase in declination “does not compensate” for the shift in sunrise and sunset to later moments on the clock. That’s why it turns out that “the day grows in the evening.”
SUN DECEMBER 2011 Bratsk (Irkutsk region)
date Sun VC Sun VC° diam. coord. (0 hours places)
19 10:43 14:09 17:36 +10° 32’30” 17:44.0 -23°23’
20 10:43 14:10 17:36 +10° 32’31” 17:48.4 -23°25’
21 10:44 14:10 17:36 +10° 32’31” 17:52.9 -23°26’
22 10:45 14:11 17:37 +10° 32’31” 17:57.3 -23°26’
23 10:45 14:11 17:37 +10° 32’31” 18:01.8 -23°26’
24 10:45 14:12 17:38 +10° 32’31” 18:06.2 -23°26’
25 10:46 14:12 17:39 +10° 32’31” 18:10.6 -23°25’
And one more thing: the moment of the solstice shifts every year, since the duration solar year does not coincide with calendar time. So, last year the winter solstice occurred on December 21 at 23.38 UTC. This is because the solar year is about 365 days and 6 hours long. Over four years, a whole day is accumulated and added to leap year, February 29 to compensate for this offset.
As you know, the Earth revolves in its orbit around the Sun. For us, people on the surface of the Earth, this annual movement of the Earth around the Sun is noticeable in the form of the annual movement of the Sun against the background of stars. As we already know, the path of the Sun among the stars is a great circle of the celestial sphere and is called the ecliptic. This means that the ecliptic is a celestial reflection of the Earth’s orbit, therefore the plane of the Earth’s orbit is also called the ecliptic plane. The Earth's rotation axis is not perpendicular to the ecliptic plane, but deviates from the perpendicular at an angle. Thanks to this, the seasons change on Earth (see Fig. 12). Accordingly, the plane of the earth's equator is inclined at the same angle to the plane of the ecliptic. The line of intersection of the plane of the earth's equator and the plane of the ecliptic retains (if precession is not taken into account) an unchanged position in space. One end of it points to the point of the spring equinox, the other - the point of the autumn equinox. These points are motionless relative to the stars (up to precessional movement!) and together with them participate in the daily rotation. Near March 21 and September 23, the Earth is positioned relative to the Sun in such a way that the boundary of light and shadow on the Earth's surface passes through the poles. And since each point on the Earth’s surface makes a daily movement around the Earth’s axis, then exactly half of the day it will be on the illuminated part of the globe, and the second half on the shaded part. Thus, on these dates, day is equal to night, and they are called the days of the spring and autumn equinoxes, respectively. At this time, the Earth is located at the intersection of the equator and ecliptic planes, i.e., at the points of the spring and autumn equinoxes, respectively. Let us highlight two more special points in the Earth’s orbit, which are called solstices, and the dates on which the Earth passes through these points are called solstices. At the point of the summer solstice, in which the Earth is close to June 22 (summer solstice day), the north pole of the Earth is directed towards the Sun, and for most of the day any point in the northern hemisphere is illuminated by the Sun, i.e. on this date the day is the longest of the year . At the point of the winter solstice, at which the Earth is close to December 22 (winter solstice day), the Earth's north pole is directed away from the Sun, and for most of the day any point in the northern hemisphere is in the shadow, i.e. on this date the night is the longest in the year, and the day is the shortest. Due to the fact that the calendar year does not coincide in length with the period of the Earth’s revolution around the Sun, the days of the equinoxes and solstices in different years may fall on different days (one day from the above dates). However, in the future, when solving problems, we will neglect this and assume that the days of the equinoxes and solstices always fall on the dates indicated above.
