Dates of solstice, equinox, add your price to the comment database. Why do equinoxes and solstice occur? Winter and summer solstice points
In the old days, the summer solstice was called the summer solstice - after this event, the day begins to shorten, the sun “turns” towards winter. They said: “The sun is for winter, summer is for heat.”
Summer solstice for the earthly observer Sergey Ov"
Fig.1 Position of the Sun on the Day summer solstice north of the Tropic of Cancer.
“The summer solstice is the longest day of the year,” this is how most respondents will answer the question: “What is remarkable about the summer solstice?”
More advanced survey participants will tell you that from the point of view of an earthly observer, on this day the Sun at noon rises to its greatest height in the sky of the Northern Hemisphere, and on this day the shadows are the shortest (Fig. 1)
But if you ask this question to an astronomer, he will answer that on this day (day) the Earth, in its orbital movement, passes the point of the summer solstice.
It turns out that the summer solstice is just a moment, a moment! And according to the basics of modern astronomy, this is indeed true.
The summer solstice point is the point in Earth's orbit at which the angle between the direction to the center of the Sun and the north of the earth's axis becomes minimal, and the plane passing through the center of the Sun and the axis of the Earth is perpendicular to the plane of the ecliptic (Diagram 1 - in addition, a separate section is devoted to this topic, for those who are interested in the astronomical aspects of this event).
Scheme 1. Planet Earth at the summer solstice point, the ecliptic plane and the tilt of the earth’s axis
Earth at the summer solstice, ecliptic and tilt of the earth's axis, mini
To enlarge the image and see explanations, click on it...
Events associated with the summer solstice
According to the Law of the Russian Federation "On the Calculation of Time" and the basics of celestial mechanics, the most common date for the summer solstice is Central Russia is June 21, only occasionally in leap years the solstice can happen on June 20, and even then thanks to the Moon (the next such event is expected 06/20/2024 23:50 MSK).
| Year | Year | Summer solstice date (MSK) | |
| 2016 | 21.06.2016 01:34 | 2020 | 21.06.2020 00:44 |
| 2017 | 21.06.2017 07:24 | 2021 | 21.06.2021 06:32 |
| 2018 | 21.06.2018 13:07 | 2022 | 21.06.2022 12:14 |
| 2019 | 21.06.2019 18:54 | 2023 | 21.06.2023 17:58 |
In 2019, the Earth will be at the summer solstice point 21 June 2019 18:54 MSK(06/21/2019 15:54 UTC - ).
At this moment the following events will occur:
1. Astronomical summer will come;
2. According to the zodiac calendar, the Sun will move into the zodiac sign Cancer;
3. The length of the day begins to decrease.
In addition, on these days:
1. This night will be the most on a short night 2019;
2. The sun rises to its greatest height in the sky of the Northern Hemisphere at noon;
3. The sun will rise and set at the northernmost points of the horizon.
On the morning of this day, in case of clear weather, a ray of sun will touch the cherished mark of the summer solstice at Stonehenge, just like in other ancient structures designed to provide calendar time.
Customs and traditions that originated during the summer solstice
Nativity of John the Baptist Orthodox calendar, established by Julius Caesar, falls on June 24; at the beginning of our chronology, the summer solstice also fell on these days...
But the trouble is, every 128 years the Julian calendar lags behind the currently accepted Gregorian calendar by one day; in 2000 thousand years since the Nativity of Christ, almost 14 days have passed, so now the Orthodox celebrate Ivan Kupala on July 7 according to the modern Gregorian calendar.
So, as we have now learned, the celebration of Ivan Kupala in former times fell on the days summer solstice. For all ancient peoples this day is not complete without special attention. The ancient Slavs celebrated the Wedding of the Sun on the first night that began to lengthen (usually from June 23 to 24), since at this time “the dawn meets the dawn.” - The wife of the Sun (Yarilo, and, accordingly, Yarilin Day) was Zarya (Zarya Zaryanitsa), according to another version, the Sun, and the heat and fire associated with it, was personified by Dazhbog (Dazhdbog), who married on this day the goddess of earth and water Mokosha . Latest version has some logical confirmation in ancient tradition, celebrating this union of the gods who control the elements of fire and water, people exposed themselves to the cleansing effects of these elements. Unfortunately, although in the early Christian period the church did not interfere with the celebration of ancient Slavic rites, it sought to provide an Orthodox basis for them. As a result, practically nothing from ancient Slavic pagan mythology has survived to this day. In addition, the pantheon of East Slavic gods mentioned in writing in ancient sources is so small that it provides the opportunity for unlimited flights of fancy in the composition of “proto-Slavic mythology” and “recreation” of the numerous pantheon of “Slavic gods”.
Based on materials from the section “Customs and Traditions of the Kupala Night” of the article:
Proverbs and sayings about the summer solstice
"The sun is for winter, summer is for heat."
"Solstice - the beginning of summer."
"In June the dawn meets the dawn"
"Before the solstice this spring, after the solstice - before the winter".
Summer solstice point
By definition, the solstice is a moment that is physically very difficult to fix (and, as a result, expensive), so it is determined by calculation using celestial mechanics, using following signs summer solstice points:
The angle between the direction to the center of the Sun and the north of the earth's axis reaches a minimum ();
- the plane passing through the center of the Sun and the axis of the Earth is perpendicular to the plane of the ecliptic ().
True, these signs are more suitable for stating the fact of the solstice than for calculating or perceiving the astronomical essence of the event - for this, stereometric criteria are more clear, and most importantly, historically reliable:
The angle between the ecliptic plane and the equatorial plane reaches a maximum: 23° 27" ();
- the line of intersection of the equatorial plane with the ecliptic plane is perpendicular to the line connecting the center of the Sun and the center of the Earth (direction to the Sun -);
- the line connecting the center of the Sun and the center of the Earth passes through the Tropic of Cancer (Northern Tropic).
Diagram 2. Summer solstice point: ecliptic plane, equatorial plane and earth's axis
Earth at the summer solstice and the tilt of the earth's axis
Diagram 2. Summer solstice point: ecliptic plane, equatorial plane and earth's axis
To enlarge the image and see explanations of the symbols, click on it...
It is no coincidence that diagram 2 shows the main axis of the Earth's orbit - line A 1 A 2.
As can be seen from the figure, the semimajor axis of the Earth's orbit OA 1 passes near the point of the summer solstice; literally in a few days the Earth will be at aphelion - the farthest point of its orbit from the Sun. In 2019, the Earth will pass aphelion 07/04/2019 22:11 MSK. Due to this relative position of the solstice point and aphelion of the Earth in the Northern Hemisphere, summers are not as hot as in the Southern Hemisphere, and winters are milder, since in winter the Sun is closer to the Earth. But this will not always be the case; in 12,900 years, the summer solstice will occur near perihelion (the point of the orbit closest to the sun), which will inevitably lead to climate change.
Earth at the summer solstice
View from near-Earth space
Earth at the summer solstice, tilt of the earth's axis (big picture)
Sergey Ov
Main sign summer solstice points.
Designations:
S summer N - line indicating the earth's axis;
∠OS summer N - the angle of inclination of the earth's axis in the direction of the Sun: at the point of the summer solstice its value reaches a minimum (66° 33");
B 1 B 2 - perpendicular to the direction of the Sun, lying in the ecliptic plane;
DC - perpendicular to the direction of the Sun, lying in the plane of the earth's axis;
∠B 1 DC - the angle between the ecliptic plane and the plane of the earth's axis.
Summer solstice
Observation from Earth
Sergey Ov
Signs of the summer solstice point, stereometry
Designations:
OS summer - a line connecting the center of the Sun and the center of the Earth (direction to the Sun);
Z 1 Z 2 - line of intersection of the equatorial plane with the plane of the earth's axis;
∠Z 1 S summer O - the angle between the ecliptic plane and the equatorial plane: at the point of the summer solstice its value reaches its maximum (23° 27");
E 1 E 2 - line of intersection of the equatorial plane with the ecliptic plane;
∠OS summer E 2 - the angle between the line of intersection of the equatorial plane with the ecliptic plane and the line connecting the center of the Sun and the center of the Earth with a straight line: 90°!
A 1 A 2 is the main axis of the Earth's orbit.
Sergey Ov(Seosnews9)
id="seasons">1. Solstice - the moment in time at which the center of the Sun passes either through the northernmost. the point of the ecliptic, which has a declination of +23° 27" (summer solstice point), or through its southernmost point, which has a declination of - 23° 27" (the point winter solstice). Near the solstice, the declination of the Sun (see Celestial coordinates) changes very slowly, since at this place its movement along the ecliptic occurs almost parallel to the equator. This is the reason why the midday altitude of the Sun remains almost constant for several days, which is why the term “solstice” is associated.
Big Soviet Encyclopedia, 3rd ed. 1969 - 1978
2. A. N. Afanasyev. Poetic views of the Slavs on nature (1869) - reprint: M., 1994
3. Aphelion - special case apocentre. Term Aphelion used to name the most distant point in the orbit celestial bodies moving around the Sun. There is a synonym: apohelium (from the Greek "Helios" - Sun). Planet Earth passes the aphelion point of its orbit on July 3-5 (depending on the relative position of the planets and the date after the February leap year correction). The calculated distance between the centers of mass of the Earth and the Sun at aphelion is 152098233 kilometers (1.0167 AU).
What do summer and winter solstices mean? Please write in more detail. Thank you.))
Solstice- the moment in time in the annual rotation of the Earth around the Sun when the shortest day or shortest night is observed. There are two solstices in the year - winter and summer. In the northern hemisphere, the winter solstice occurs on December 21 or 22 and then the shortest day (and the longest night) is observed, and the summer solstice occurs on June 21 or 22 and then the shortest night (and the longest day) is observed. IN southern hemisphere on specified dates The summer and winter solstices occur, respectively.During several adjacent days of the solstice, the Sun almost does not change its declination, its midday heights in the sky are almost unchanged; This is where the name of the solstice comes from.
On June 22, being in the constellation Gemini, the Sun has its greatest height above the horizon. In the northern hemisphere, this is the longest day of the year and the shortest night. For several days in a row, the Sun seems to stand in one place, which is why these days are called days summer solstice. These are the hottest days of the year.
In mid-latitudes, the length of the day exceeds 16 hours; the sun does not set at all above the Arctic Circle. Accordingly, the night will last less than 7 hours.
Despite the fact that summer is just beginning to gain strength from now on, the sun is already turning towards autumn. After the solstice, the daylight hours will become shorter, and by September 23 - the day of the autumnal equinox - dark time day will prevail over light.
According to experts, nature also reacts very strongly to the solstice - before this day, as a rule, all plants try to reach maximum growth, and after the summer solstice they use the accumulated forces, we can say that nature stretches out on this day.
Around the date of December 22, the Sun rises to its lowest height above the horizon for several days. These days are called days winter solstice. The northern hemisphere of the Earth experiences the shortest days and longest nights of the year. December 22 is considered the beginning of astronomical winter. Daylight hours are increasing, which means spring is just around the corner. . After December 22, the Sun is at least “at a bird’s leap”, but it increases in altitude. For ancient people it was a divine miracle - the victory of light over darkness. Daylight hours are increasing, which means spring is just around the corner.
Now in my city, there is such a phenomenon as White Nights, I love this time)))
White nights are bright nights, when the evening twilight merges with the morning twilight, and the darkness of the night does not occur. White nights are observed in both hemispheres at latitudes above 60 degrees.
In this case, the longest or shortest day is observed. In the northern hemisphere, the winter solstice occurs on December 21 or December 22 and then the shortest day (and the longest night) is observed, and the summer solstice occurs on June 20 or 21 and then the longest day (and the shortest night) is observed. In the southern hemisphere, these dates fall on the summer and winter solstices, respectively.
In mid-latitudes, throughout the year in spring and early summer, the Sun rises higher and higher above the horizon every day at noon, and on the day of the summer solstice it “stops” and reverses its movement. Then every day at noon it drops lower and lower and finally, at the moment of the winter solstice, it again reverses its movement and begins to rise.
Due to the leap shift, solstice dates fluctuate by 1-2 days. The summer solstice usually occurs on June 21, the winter solstice on December 22. In astronomy, the moment of the winter solstice is taken to be the beginning of winter, and the moment of the summer solstice is the beginning of summer. The astronomical longitude of the sun at these moments is, respectively, 90° and 270°, and in astrology this means the entry of the Sun into the sign of Cancer (summer solstice) and Capricorn ().
For several days before and after the solstice, the Sun almost does not change its declination, its midday heights in the sky are almost unchanged (the height changes throughout the year according to a graph close to a sinusoid); This is where the name of the solstice comes from. From observations of the heights of the Sun during both solstices, the inclination of the ecliptic plane to the plane of the celestial equator can be determined.
Solstice
Solstice (solstice) is the Old Russian name for the solstice. Corresponded to the moment the Sun “turned” towards profit or decline of the day.
In Rus' and in many European countries The day of the winter solstice was celebrated as a celebration of the birth of the sun.
Read also - Yule (medieval winter solstice festival among the Scandinavian and Germanic peoples).
Ivan Kupala
Ivan Kupala, also Midsummer's Day, is a pagan folk holiday celebrated in Russia, Belarus, Poland, Lithuania, Latvia, Estonia and Ukraine on the summer solstice. Ivan Kupala is celebrated on June 24 (according to the Julian calendar), taking into account the natural and historical factor of the solstice. Also, Ivan Kupala is celebrated by many on July 7 (this day, according to the current Gregorian calendar, corresponds to June 24 according to the Julian calendar). Midsummer's Day has an ancient tradition of celebration throughout almost all of Europe.
Henryk Semiradsky. Night on Ivan Kupala
Etymology
The name of the holiday arose as a result of the gradual imposition (in the process of Christianization) of the name church day in memory of John (Ivan) the Baptist (John the Baptist) on the ancient pre-Christian (Slavic) holiday of Kupala, dedicated to pagan god Kupala, which is calendar, and is dedicated to the shortest night (June 21-22). Previously, the holiday was called Kupa, the same root as the word together, meaning unity.
About the holiday
Midsummer's day is filled with rituals associated with water, fire and herbs.
Kupala day - Chram Mazowiecki RKP (2009)
Water
Swimming on Midsummer's Day is a national custom, but in some areas peasants considered such swimming dangerous, since on this day the birthday boy is a merman himself, who cannot stand it when people interfere in his kingdom, and takes revenge on them by drowning anyone unwary. On this holiday, by folk beliefs, water can be “friends” with fire, and their union is considered a natural force.
Fire
main feature Kupala night - cleansing bonfires. People danced around them and jumped over them: whoever jumps more successfully and higher will be happier. In some places, livestock was driven through the Kupala fire to protect it from pestilence. In the Kupala bonfires, mothers burned the shirts taken from their sick children, so that illnesses would be burned along with this linen. Young people and children, jumping over the fires, made noisy funny Games and running a race. We definitely played burners. According to peasant beliefs, in Kupala, the most short night, you cannot sleep, as all evil spirits come to life and become especially active - witches, werewolves, mermaids, snakes, sorcerers, brownies, water creatures, goblins.
Herbs
Characteristic sign Ivan Kupala - numerous customs and legends associated with the plant world. Herbs and flowers collected on Midsummer's Day are placed under Midsummer's dew, dried and preserved, considering such herbs to be more healing. They fumigate the sick, fight evil spirits, throw them into a flooded oven during a thunderstorm to protect the house from a lightning strike, and use them to kindle love or to “dry it out.”
The main character flora On Midsummer's Day, a fern appeared, with which legends about treasures were universally associated. With a fern flower opening for just a few moments at midnight on Midsummer, you can see all the treasures, no matter how deep in the ground they are. In pre-revolutionary Russia, Ivan Kupala was one of the most revered and important holidays of the year, the entire population took part in it, and tradition required the active inclusion of each participant in the celebration in all rituals and the mandatory implementation of a number of rules, prohibitions and customs.
In Latvia, this holiday is still the most revered and popular, and even more popular than Christmas and New Year. Here it is called "Ligo" or "Jan's Day". June 23-24 are public holidays, and the entire population of the country (both the Latvian and the Russian part) rushes to dachas, vegetable gardens and the banks of various reservoirs to fry kebabs and light fires until the morning. On these days, half the annual norm of beer is drunk [source not specified 285 days], and the intensified “search for the fern flower” annually leads to a surge in the birth rate in March.
Signs and customs
1. On the night before Ivan Kupala, the girls lower wreaths with lit splinters or candles onto the river waves; they make wreaths from Ivan da Marya, burdock, virgin grass and bear's ear. If the wreath sinks immediately, it means that the betrothed has fallen out of love and cannot marry him. The one whose wreath floats the longest will be the happiest, and the one whose wreath burns the longest will live a long, long life!
2. On Midsummer night, witches become more dangerous, and therefore you should place nettles on the threshold and on windowsills to protect yourself from their attacks. It is necessary to lock the horses so that the witches do not steal them and ride them to Bald Mountain: the horse will not return from there alive!
3. It’s night in Ivanovo ant heaps They collect oil in a vessel, which is recognized as a healing agent against various ailments.
4. On Kupala night, trees move from place to place and talk to each other through the rustling of leaves; Animals and even herbs talk to each other, which are filled with special, miraculous power that night.
5. If on this night you pick the Ivan da Marya flower and put it in the corners of the hut, the thief will not approach the house: brother and sister (yellow and purple flowers of the plant) will talk to each other, and the thief will think that the owner and mistress are talking.
6. At midnight, without looking, you need to pick flowers and put them under your pillow, and in the morning check whether you have collected twelve different herbs. If you have enough, you will get married this year. They place a triputnik (plantain) under the head, saying: “Triputnik-fellow traveler, you live along the road, you see young and old, say my betrothed!”
7. If you climb twelve gardens on Midsummer Day, any wish will come true.
I.I. Golikov. Fortune telling on wreaths. Palekh, 1920s
Winter Solstice and Cultural Tradition
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. 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).
The Semitic predecessor of the “holiday of light” - Hanukkah - is also supposedly associated with the solstice.
| Dates and times of solstices and equinoxes in UTC-0 (for Kyiv time +2 hours) |
||||||||
|---|---|---|---|---|---|---|---|---|
| year | Equinox March |
Solstice June |
Equinox September |
Solstice December |
||||
| day | time | day | time | day | time | day | time | |
| 2010 | 20 | 17:32 | 21 | 11:28 | 23 | 03:09 | 21 | 23:38 |
| 2011 | 20 | 23:21 | 21 | 17:16 | 23 | 09:04 | 22 | 05:30 |
| 2012 | 20 | 05:14 | 20 | 23:09 | 22 | 14:49 | 21 | 11:12 |
| 2013 | 20 | 11:02 | 21 | 05:04 | 22 | 20:44 | 21 | 17:11 |
| 2014 | 20 | 16:57 | 21 | 10:51 | 23 | 02:29 | 21 | 23:03 |
| 2015 | 20 | 22:45 | 21 | 16:38 | 23 | 08:20 | 22 | 04:48 |
| 2016 | 20 | 04:30 | 20 | 22:34 | 22 | 14:21 | 21 | 10:44 |
| 2017 | 20 | 10:28 | 21 | 04:24 | 22 | 20:02 | 21 | 16:28 |
| 2018 | 20 | 16:15 | 21 | 10:07 | 23 | 01:54 | 21 | 22:23 |
| 2019 | 20 | 21:58 | 21 | 15:54 | 23 | 07:50 | 22 | 04:19 |
| 2020 | 20 | 03:50 | 20 | 21:44 | 22 | 13:31 | 21 | 10:02 |
Solstice- an astronomical event, the moment of passage of the center of the Sun through the points of the ecliptic, most distant from the equator of the celestial sphere and called solstice points.
The position of the Earth in orbit at the moments of: summer solstice, winter solstice, autumn equinox and spring equinox
Distinguish winter And summer solstice. Universal time (in other time zones these dates may differ by a day) in the northern hemisphere winter The solstice occurs on December 21st or 22nd, and summer The solstice occurs on June 21 (in leap years, June 20 or 21). In the southern hemisphere, on the contrary, the December solstice turns out to be summer, and June - winter.
The winter solstice is the most short day(from the very long night) per year in the corresponding hemisphere (except for the pole region, where the only night of the year lasts six months, and the winter solstice is the middle of this polar night). The summer solstice is the longest day (with the shortest night) of the year in the corresponding hemisphere (except for the polar region, where the only daylight in the year lasts six months and the summer solstice is the middle of this polar day).
In mid-latitudes, during astronomical winter and spring, the point at which the Sun is at noon (more precisely, at true noon), rises higher above the horizon every day, and on the day of the summer solstice it “stops” and reverses its movement. Then every day it sinks lower and lower, and, in the end, at the moment of the winter solstice, it “stops” again and begins to rise back.
Due to leap shift solstice dates in different years may differ by 1-2 days. Traditionally, the moment of the winter solstice is taken as the beginning of astronomical winter, and the moment of the summer solstice is taken as the beginning of astronomical summer, which is a consequence of the choice for the beginning astronomical spring or autumn - a spring or autumn day equinox. The astronomical longitude of the sun at these moments is, respectively, 90° and 270°.
For several days before and after the solstice, the Sun almost does not change its declination, its midday heights in the sky are almost unchanged (the height changes throughout the year according to a schedule close to the bell-shaped top of a sine wave); This is where the name of the solstice comes from. From observations of the heights of the Sun during both solstices, the inclination of the ecliptic plane to the plane of the celestial equator can be determined.
Point designation
The points of the winter and summer solstices are designated by zodiac symbols corresponding to the constellations in which they were located at the time of Hipparchus: the winter solstice - the sign of Capricorn (♑), the summer solstice - the sign of Cancer (♋). As a result of the anticipation of the equinoxes, these points have shifted and are now located, respectively, in the constellations Sagittarius and Taurus, and the summer solstice point moved to the constellation Taurus from the constellation Gemini relatively recently - in the fall of 1988.
Winter solstice
Winter solstice occurs at the moment when the tilt of the Earth's axis of rotation in the direction from the Sun takes highest value. The maximum angle of inclination of the earth's axis relative to the Sun during the solstice is 23° 26".
Chart of seasons in the northern hemisphere of the Earth. Far right: winter solstice
It is more obvious for residents of high latitudes that the winter solstice occurs on the shortest day and longest night of the year, when the height of the sun in the sky is at its lowest. Because the winter solstice lasts only a short moment, other names are used for the day when it occurs, such as “midwinter,” “longest night,” or “first day of winter.”
The seasonal significance of the winter solstice is the reversal from the gradual lengthening of the night and shortening of the day to reverse direction. Depending on the calendar shift, the winter solstice occurs on December 21 or 22 in the Northern Hemisphere and June 20 or 21 in the Southern Hemisphere.
IN different cultures the interpretation of this event was perceived differently, but among most peoples it was regarded as a revival, and holidays, festivals, meetings, rituals and other celebrations were held at this time.
In 45 BC. e. Julius Caesar in his Julian calendar established for Europe December 25 as the date of the winter solstice (lat. Bruma).
Bust of Julius Caesar from the National Archaeological Museum in Naples. Created approximately during the reign of Trajan (early 2nd century AD)
Since then, due to the difference between the calendar year (365.2500 days) and the tropical year (~365.2421897 days), there has been a shift in the actual astronomical solstice by about three days every four centuries, reaching the date of December 12 in the 16th century. In 1582 the Pope Gregory XIII decided to restore exact correspondence between the seasons and civil year, but at the same time he referred not to the era of the Roman emperor, but to the Council of Nicea in 325, the period of the formation of the main Christian holidays.
Gregory XIII
Thus, the Pope annulled the 10-day error accumulated during the period from the 4th to the 16th centuries, but did not take into account the 3 days that accumulated between the 1st and 4th centuries AD. This calendar adjustment pushed the winter solstice in the northern hemisphere to around December 22nd. Still in Gregorian calendar The solstice fluctuates by one or two days, and in the long term there may be an additional shift of one day every 3,000 years.
Historical and cultural significance
Solstice may have been a special moment in the annual cycle, even in times Neolithic
Neolithic sign - Gosek circle. The yellow lines point to sunrise and sunset on the winter solstice.
The astronomical events that have since ancient times governed the mating of animals, the planting of crops, and the storage of winter supplies until the next harvest, show how various cultural myths and traditions arose. This is evidenced by the layout of archaeological sites of the late Neolithic and Bronze Age, such as Stonehenge in the UK and Newgrange in Ireland.
Stonehenge
Newgrange
The main axes of both of these monuments were carefully aligned along a visual line indicating the winter solstice sunrise (Newgrange) and the winter solstice sunset (Stonehenge). In relation to Stonehenge, the significant fact is that the Great Trilith is turned outward from the center of the monument, that is, its flat front part faces the middle of winter along the Sun.
Japanese Sun Goddess Amaterasu emerging from a cave
The winter solstice was extremely important in the life of the primitive community, since people were not sure that they had been well prepared for winter during the previous nine months, and that they would be able to survive this winter. Famine was common during the winter months, from January to April, a period of the year known as the famine months. IN temperate climate The Midwinter Festival was the last festival before the hard winter period began. Most of the livestock were slaughtered at this time, as there was nothing to feed them during the winter, so the winter solstice was the only period of the year when the most was consumed fresh meat. At that time most of The wine and beer made during the warm season were finally ready and ready to drink. Celebrations were held not only on this day itself, they began at midnight or at dawn, and most often the day before.
Since the winter solstice is a turning point in the presence of the Sun in the sky, it gave rise to the widespread emergence of the concept of the birth or rebirth of gods. In many cultures, cyclical calendars are based on the winter solstice, celebrating the resurgent year, a symbol of “new beginnings,” such as the cleansing tradition of Hogmanay in Scotland. IN Greek mythology gods and goddesses celebrated the winter and summer solstices, on these days the god Hades was allowed to appear on Mount Olympus (his kingdom was underworld, and at any other time he was not supposed to leave there).
Direct observation of the solstice by amateurs is difficult because the sun moves towards the solstice point quite slowly, so that it is difficult to determine its specific day, let alone its instant. Knowing the time of an event's origin has only recently become possible down to almost an instant thanks to precise tracking of astronomical data. The actual moment of the solstice cannot be detected by definition (you cannot notice that the object has stopped moving, you can only state that in the current measurement the object has not changed its position compared to the previous measurement, or has moved in the opposite direction). In addition, in order to determine an event with an accuracy of one day, one must be able to observe changes in azimuth and altitude less than 1/60 of the angular diameter of the Sun. A similar determination with an accuracy of up to two days is easier; it requires an observation error of only about 1/16 of the angular diameter of the Sun. Thus, most observations indicate the day of the solstice, and not its instant. This is often done by observing the sunrise and sunset, using an astronomically calibrated instrument that ensures that a beam of light passes to a certain point at exactly the right moment in time.
Sunrise between the stones at Stonehenge on the winter solstice in the mid-1980s
Summer solstice
Summer solstice occurs at the moment when the tilt of the Earth's axis of rotation in the direction from the Sun takes on its smallest value.
Chart of seasons in the northern hemisphere of the Earth. Top left position: summer solstice
It is more obvious to residents of high latitudes that the summer solstice occurs on the longest day and shortest night of the year, when the sun rises at its highest in the sky. Because the summer solstice lasts only a brief moment in time, other names are used for the day on which the summer solstice occurs, such as “midsummer,” “longest day,” or “first day of summer.”
Depending on the calendar shift, the summer solstice occurs on June 20 or 21 in the Northern Hemisphere and December 21 or 22 in the Southern Hemisphere.
The day is widely celebrated by different peoples.
Equinox
Equinox - an astronomical phenomenon representing the moment when the center of the Sun, in its apparent movement along the ecliptic, crosses the celestial equator.
When observing the Earth from space, at the equinox, the terminator passes along the geographic poles of the Earth and is perpendicular to the Earth's equator.
The celestial equator is inclined at 23°26’ to the ecliptic plane
Celestial equator- a great circle of the celestial sphere, the plane of which is perpendicular to the axis of the world and coincides with the plane of the earth's equator. The celestial equator divides the celestial sphere into two hemispheres: North hemisphere, with its summit at the north celestial pole, and Southern Hemisphere, with top at south pole peace. The constellations through which the celestial equator passes are called equatorial.
Since the Earth's axis of rotation deviates from the perpendicular to the plane of the Earth's orbit by 23°26', the plane of the celestial equator is inclined at the same angle to the plane of the ecliptic. The ecliptic intersects with the celestial equator at the spring and autumn equinoxes.
The celestial equator is the basis of the equatorial celestial coordinate system: declination is measured from it (analogous geographical latitude, measured from the earth's equator). Another coordinate of this system—right ascension (analogous to geographic longitude)—is measured from the point of the vernal equinox.
Distinguish spring And autumn equinox. Universal time (in other time zones these dates may differ by a day) in the northern hemisphere spring The equinox occurs on March 20, when the Sun moves from the southern to the northern hemisphere, and autumn The equinox occurs on September 22 or 23, when the Sun moves from the northern to the southern hemisphere. In the southern hemisphere, on the contrary, the March equinox is considered autumn, and September - spring.
On the days of the equinox, over the entire surface of the Earth (excluding the areas of the Earth's poles), the day is almost equal to night(“almost”: on the days of the equinox, on the entire surface of the Earth, day is slightly longer than night; the reasons for this are atmospheric refraction, which somewhat “raises” the solar disk for the observer, and the fact that the length of the day is defined as the difference between the moments of sunset and sunrise, which, in turn, are determined by the position top edge solar disk relative to the horizon, while the equinox is considered relative center solar disk). On the days of the equinox, the Sun rises almost exactly in the east (several north of east) and sets almost exactly in the west (slightly north of west).
During the period when the day is longer than the night, approximately from the spring to autumn equinox, the Sun rises north of the east and sets north of the west (strictly speaking, this period begins shortly before the spring equinox and ends shortly after the autumn equinox), and during the period when the day is shorter than the night , which lasts approximately from the autumn to the spring equinox, the Sun rises south of the east and sets south of the west (strictly speaking, this period begins shortly after the autumn equinox and ends shortly before the spring equinox).
The points of intersection of the celestial equator with the ecliptic are called points of the equinoxes. Due to the ellipticality of its orbit, the Earth moves from the autumn equinox to the spring equinox rather than from the spring to the autumn point. Due to the precession of the earth's axis mutual arrangement the equator and ecliptic changes slowly; this phenomenon is called anticipation of the equinoxes. Over the course of a year, the position of the equator changes so that the Sun arrives at the equinox 20 minutes 24 seconds earlier than the Earth completes its full orbit. As a result, the position of the equinoctial points on the celestial sphere changes. From the point of the vernal equinox, right ascensions along the celestial equator and longitudes along the ecliptic are counted. Determining the position of this fictitious point on the celestial sphere is one of the main tasks of practical astronomy. The points of the spring and autumn equinoxes are designated by zodiac symbols corresponding to the constellations in which they were located at the time of Hipparchus (as a result of the anticipation of the equinoxes, these points shifted and are now located, respectively, in the constellations Pisces and Virgo): the spring equinox - the sign of Aries (♈), the autumn equinox - the sign of Libra (♎).
In addition, both equinoxes are a feature that changes the vector of correlation between latitude and duration daylight hours to the opposite. That is, during the period from the spring equinox to the autumn, the duration of daylight hours is more northern latitude exceeds that in the more southern one, and in the period from autumn to spring, on the contrary.
Spring and autumnal equinox are considered the astronomical beginning of the seasons of the same name. The interval between two equinoxes of the same name is called tropical year which is adopted for measuring time. A tropical year has approximately 365.2422 solar days, so the equinox falls on different time days, moving forward each time by almost 6 hours. The Julian year consists of 365¼ days. The intercalary day of a leap year returns the equinox to the previous date of the year. But the tropical year is slightly smaller than the Julian year, and the equinox actually recedes slowly according to the numbers of the Julian calendar. In the Gregorian calendar, due to the omission of 3 days in 400 years, it is almost motionless (the Gregorian year averages 365.2425 days).
The modern Gregorian calendar is designed so that, over the long term, the equinoxes fall on the same dates. However, slight fluctuations in the dates of the equinoxes do occur. The earliest dates of the equinoxes occur in leap years, and the latest dates occur in years before leap years.
During the existence of the Gregorian calendar, the record earliest equinoxes occurred in 1696: March 19, 15:5 am - spring and September 22, 3:8 am - autumn; and the latest in 1903: March 21, 19:15 - spring and September 24, 5:45 - autumn.
In the next 100 years, the earliest equinoxes will be in 2096: March 19 14:7 m - spring and September 21 22:58 m - autumn (which will be a record for early equinoxes for 400 years); and the latest in 2103 are March 21, 6:27 a.m.—spring and September 23, 3:28 p.m.—autumn.
Speaking about the dates of the equinox, one should distinguish between a date according to universal time and a date for a specific time zone: if the equinox occurs before 24:00 universal time, in countries located west of the prime meridian, the next day has not yet arrived and the occurrence there will be considered according to local time equinox 1 day earlier; if the equinox occurs later than 24:00 universal time, then in countries located east of the prime meridian, the next day will already have arrived and the date of the equinox will be 1 more.
It should also be noted that, according to the creators of the Gregorian calendar, the “official” date of the vernal equinox is March 21 (literally “12 days before the Kalends of April”), since this was the date of the vernal equinox during the Council of Nicaea.
Last time in this century the vernal equinox fell on March 21 in 2007 and will continue to fall on March 20 or even March 19 in the 21st century.
Peoples and religions that have New Year begins at the equinox
Iran, Afghanistan, Tajikistan, Uzbekistan, Turkmenistan, Kyrgyzstan, Bahai-Navruz, Azerbaijan, Kazakhstan.
The bas-relief in Persepolis is a symbol of the Zoroastrian Nowruz - on the day of the spring equinox, the forces of the eternally fighting bull, personifying the Earth, and the lion, personifying the Sun, are equal
Leap year
Leap year (lat. bis sextus- “second sixth”) is a year in the Julian and Gregorian calendars, the duration of which is 366 days - one day longer than the duration of a regular, non-leap year. In the Julian calendar, every fourth year is a leap year; in the Gregorian calendar there are exceptions to this rule.
Introduction history
From January 1, 45 BC. e. The Roman dictator Gaius Julius Caesar introduced a calendar developed by Alexandrian astronomers led by Sosigenes, which was based on the fact that the astronomical year is approximately equal to 365.25 days (365 days and 6 hours). This calendar was named Julian In order to equalize the six-hour offset, it was introduced leap year . Three years were counted as 365 days, and for each year divisible by four, one additional day was added in February.
In the Roman calendar, days were counted in relation to subsequent ones. Kalends(first day of the month), nonam(5th or 7th day) and idam(13th or 15th day of the month). Thus, the day of February 24 was designated as ante diem sextum calendas martii(“sixth day before the Kalends of March”). Caesar decided to add a second sixth to February ( bis sextus) the day before the March calendar, that is, the second day of February 24. February was chosen as last month Roman year. The first leap year was 45 BC. e.
Caesar was assassinated two years after the introduction of the new calendar, and the second leap year began after his death. This may explain the fact that the priests in charge of the calendar did not understand the principle of introducing an extra day every fourth year, and instead began introducing an extra day in February every third year (it is assumed that they were counting the fourth from the year preceding the leap year). . For 36 years after Caesar, every third year was a leap year, and only then did Emperor Augustus restore the correct order of leap years (and also abolish several subsequent leap years to remove the accumulated additional shift). From a comparison of Roman and Egyptian dating in a papyrus found in 1999, it was established that leap years in Rome were 44, 41, 38, 35,32, 29, 26, 23, 20, 17, 14, 11, 8 years before n. e., 4, 8, 12 and every fourth year thereafter.
Gregorian calendar
The length of the tropical year (the time between the two spring equinoxes) is 365 days 5 hours 48 minutes 46 seconds. The difference in the length of the tropical year and the average Julian calendar year (365.25 days) is 11 minutes 14 seconds. From these 11 minutes and 14 seconds, one day is added up in approximately 128 years.
After several centuries, a shift in the day of the vernal equinox, which is associated with church holidays. TO XVI century the vernal equinox occurred approximately 10 days earlier than March 21, which is used to determine the day of Easter.
To compensate for the accumulated error and avoid such a shift in the future, in 1582 Pope Gregory XIII carried out a calendar reform. To average calendar year corresponded better to the solar one, it was decided to change the rule of leap years. As before, a year whose number was a multiple of four remained a leap year, but an exception was made for those that were a multiple of 100. Such years were leap years only when they were also divisible by 400.
In other words, a year is a leap year in two cases: either it is a multiple of 4, but not a multiple of 100, or a multiple of 400. A year is not a leap year if it is not a multiple of 4, or it is a multiple of 100, but not a multiple of 400.
Last years of centuries ending with two zeros, in three cases of four are not leap days. Thus, the years 1700, 1800 and 1900 are not leap years, since they are a multiple of 100 and not a multiple of 400. The years 1600 and 2000 are leap years, since they are a multiple of 400. The years 2100, 2200 and 2300 are not leap years. In leap years, an additional day is introduced - February 29.
The last leap year was 2012, the next one will be 2016.
Jewish calendar
In the Jewish calendar, a leap year is a year to which a month is added rather than a day. The reason for this is that the Jewish calendar is based on lunar month, and therefore a year of twelve months lags behind the astronomical solar year by about 11 days. To equate lunar years A leap year of thirteen months was introduced to the solar year. The 19-year cycle includes 12 common years and 7 leap years.
Engraving by William Hogarth with the slogan "Give us back our eleven days!", 1755