Time of day on the clock Morning day evening. How many days start? Specification of temporary intervals

The antipyretic agents for children are prescribed by a pediatrician. But there are emergency situations for fever when the child needs to give a medicine immediately. Then parents take responsibility and apply antipyretic drugs. What is allowed to give to children of chest? What can be confused with older children? What kind of medicines are the safest?

How much is a day? A strange question: since childhood, we know that the day is exactly 24 hours, or 1440 minutes or 86400 seconds. So, not so. The day is the period of time for which the Earth makes one full turn around its axis, and it turns out to never occupy exactly 24 hours.

How many last day?

If you take a distant star for the reference point, and for days to consider the gap for which it will return to the same point, it turns out that one turnover of our planet takes 23 hours 56 minutes and 4 seconds! That is, in the day, the astronomical midnight can wage almost 4 minutes! Moreover, this period is called by stellar days depending on the friction caused by synoptic situations, tides / lowers and geological events change all the time in the range of up to 50 seconds. If you take our sun for reference point, as the ancestors did, then the number is already obtained closer to 24 hours. This is called the sunny day. On average, for the year, taking into account the turnover of the planet around the Sun, the sunny day for a split second in short, than twenty-four hours.

When these discrepancies revealed with the help of the most accurate atomic hours, it was decided to override a second as a fixed share of the "sunny" day, more precisely, a million-scenes-forty-fading.

The new second was in use in 1967 and was defined as "time interval equal to 9,192,631,770 radiation periods corresponding to the transition between two ultra-thin levels of the main state of the cesium atom-133 in the absence of perturbation by external fields." More precisely, you can not say - it is only painful to disappear all this at the end of a long day.

The new definition of a second means that the sunny day is gradually shifted in relation to atomic. As a result, scientists had to be introduced into the atomic year the so-called "leap second" (or "second coordination") in order to coordinate atomic year with sunny.

From 1972, a leap second was added 23 times. Imagine, otherwise, our days would have increased almost half a minute. And the land continues to slow down its rotation. And, according to scientists, in the XXIII century, in our days there will be 25th hours.

The last time the "leap second" was added on December 31, 2005 to indicate the International Service for Establishing the Rotation Parameters and the Earth Coordinates Based in the Paris Observatory.

Good news for astronomers and those of us who love when the clock go pace with the movement of the Earth around the Sun, but a headache for computer programs and all the equipment that stands on space satellites.

The idea of \u200b\u200bentering a "leaping second" met a decisive reference from the International Union of Telecommunications, who even made an official proposal to completely cancel it in December 2007.

You can, of course, wait until the difference between universal coordinated time (UTC) and middle time in Greenwich (GMT) reaches exactly an hour (somewhere after 400 years) and then put everything in order. But as long as the debate around what is considered "real" time, continues.

We master the most commonly common concepts in early childhood. Despite the age of turning, it is unlikely that any of the kids require an academic explanation to the simplest concepts - Mom can explain everything literally on the fingers, simple words. For example, "Day is when the sun shines" or "when you walk, and not sleep in the crib." Explanations are imperceptibly accumulated and systematized by forming an understanding of the term.

The meaning of the word "day"

If you look at the planet from the side, you can see quite clear separation on the day and night side. Formally, the simplest explanation is faithful from the point of view of astronomy - the day is considered to be when the light from the star falls on the surface of the planet, around which this planet rotates.

We believe that the day is a bright day of day, and the weather does not play roles. Somewhere there, above the clouds, the sun still shines, therefore, no night, around is not dark. In the same latitudes, this particular principle is observed - such concepts as a "polar day" and "polar night" are based on natural illumination.

In some cases, I mean time at all. For example, when they say "these were sad days" or "in those distant days", we are talking about some distant time in the past, when there were some events.

Division of day

Theoretically, if you rely precisely for the presence of the sun in the sky, the day is divided into two relatively equal parts - day and night. In practice, it turns out that there are morning and evening, which in one degree or another are also highlighted. Morning begins when the scan of the approaching sun appears in the sky, although the night continues formally. When the sun appears above the horizon, the dawn begins, the morning continues and lasts a few more hours while the sun rises to Zenith.

In most cases, the day is the time from about noon to the evening, when the sun begins to decline over the horizon in the West. At the same time they say "ten o'clock in the morning", but "eleven hours of the day", and even in this case options are possible.

How many hours do the day last?

Between the morning and in the evening passes on average six hours, and this is an approximate time. It turns out that day is the whole fourth part of the day. The rest of the time is occupied at night and intermediate states - in the morning and evening.

If the clarifying adjective is added to this, it becomes easier to determine what it is specifically a question. For example, a "light day" clearly indicates that we are talking about the light of the day of day when the additional sources of artificial lighting are not required. Explaining what day is, it is desirable to immediately arrange accents and clarify that much depends on the specific situation and context, otherwise mutual misunderstanding may appear.

Often the length of the day is determined not by the actual number of hours and not the duration of natural lighting, but extremely subjective sensations. A long or even endless day means that either a person cannot wait for the evening, or managed to perform many different tasks.

Specification of temporary intervals

Often the word "day" is used in the meaning of the "day". For example, "you have three days to eliminate the shortcomings." In the "day" value, this word is used when you need to specify a sufficiently long amount of time.

If you want to put some framework, it can be a "working day" - interpretation in this case provides that weekends and holidays are not considered. In working days, business commitments are taken into account - the execution of orders, the receipt of funds to the bank account and so on. The obsolete concept of "workshop" is similar to the value, this is a unit of collective farmers' work for subsequent payment. When they say "weekends", they mean a day free from all kinds of labor duties, time designed to relax.

Trying to understand what day in the presentation of another person, we usually try to simplify mutual communication as much as possible. Therefore, when we are told "Call tomorrow day," it is better to clarify, at what time interval will be appropriate. For someone and eight o'clock in the morning - the day, and someone else sleeps. If you do not specify, then on the business etiquette the day is considered an average of 11 am to 16 pm, and a good tone will be signed at about the middle of this gap. In other cases, it is better to ask to specify the exact time.

In ancient Russian sources, there is no term "SUTASI". Instead of the latter, the word "day" was used. At the same time, the day (in the meaning of the day) was divided into two parts (light and dark): a day in his own sense of the word and night.

It is difficult to accurately establish when IA Rusi went into use time measuring clock time. In ancient sources, the word "hour" is often found not only in the sense of a time unit (\u003d 1/24 days), a in the value of an indefinite moment (for example, "death hour"). But along with this in a number of sources, we find 24-hour division of the day. Every hour contained 6 "fractional chapels" or 60 "chas." Thus, an hour means a minute. There were long and instruments for measuring time. Already from the beginning of the XV century. We have reached the first description of the mechanical watches: "The Grand Duke conceived to arrange a private one and submitted him in his yard for the church of St. Annunciation.

This privately wore the rank level (clock measurement instrument). Every hour a hammer hit in the bell, which appeared and the night and daytime calculated hours. Not a man hit, but no matter how his man's hand was committed by Evon. It was arranged with the help of a man-precious mind, extremely skillfully and cunning. "Master and artist who created this device was a Serbian exhaust, - by name Lazar. The price of" chacinika "exceeded 150 rubles.

Acquaintance with the system of the ancient-Russian score of the clock is necessary because it was different from the time accepted in our time and, because of this, the sources on the sources of the day require the transfer to their respective hours, according to the modern division of the day.

With a daily measurement of time in ancient Russia, people proceeded from observations over the natural change of day and night and brought them to contact with the clock of church services.

The day began not at midnight, as is customary now, but during the period of people getting up from sleep and appeal to ordinary activities. This coincided with the morning worship service ("Sautrey"), which began before the glow and ended until sunrise. Prince XII century. Vladimir Monomakh wrote in the "teaching" to his children: "Let the sun will not find you in bed. So I did my father and all the good men: I gave God to God, I saw the sun and glorifying God with joy, I discovered the Council with a friend, Or judged people, or drove to hunt ... ".

Thus, from the first hour of the day (in the ancient-Russian account), people appealed to their next cases. Time from 3 hours before the "noon" -ceid "lunch". During this period, the Church served "Lunch". "Noon" came in 6-7 hours. Before sunset, the next church service was happening - "Evening", and the time of the day after the "evening" was adjacent in the evening. The night stretched from the end of twilight to the first signs of dawn.

In the ancient-Russian sources, the time for which one or another event falls is often indicated not in hours, but in church services. Therefore, it was necessary to stop them.

In church calendars, the distribution of the "daytime" and "night" hours was unequal for different months, as well as their units. If the day in our day is equal to the midst of the night throughout the year (12 hours. + 12 hours), and the score of the clock is carried out solid (1 -24), then in ancient Russia, depending on any number and month, the duration of the day (and respectively and nights) ranged from 7 to 17 hours. These oscillations depended on the natural shift of the dark and light parts of the day A connection with the change of natural phenomena.

The compliance of the clock over the ancient-Russian measurement of time adopted in the XVI-XVII centuries, and later calculus (XIX century) is given in Table XI.

When using sources, it should be borne in mind that in a number of areas (for example, in Novgorod), the score of the clock was different from Moscow.

Talk to the child about the days.

Do you know what a day are about?

From night and day. No wonder the saying: "Day and night - a day away." In days 24 hours. During this time, the planet Earth makes one full turn around its axis.

Do you know what a globe is and what does he look like?

This is a globe model. The globe can rotate around the axis passing through his center, as well as the Earth rotates around its invisible axis.

On the part of our planet, which is not lit by the sunshine, the night reigns, and on the illuminated part of the earth shines a bright day. The Earth rotates continuously, so day and night replace each other.

A few centuries ago, the life of people leaks in a more measured and slow pace. After all, there were no cars, no aircraft, no electric trains, no television communications, nor radio, no television. From the city to the city, people traveled on horseback for several days, weeks or months, depending on the distance.

Special accuracy in determining the time in everyday life was not needed. Therefore, the time of day was determined by about - morning, day, evening, night.

The peasons learned the time to ring church bells or the position of the sun.

Important cases usually started in the morning. No wonder in the proverb says: "The morning of the evening is wiser."

Listen to the poem "What is a day?"

Remember, son, remember, daughter,
Day is a day and night.

Day light and sun shines,
Children play in the yard:
Then take off on the swing,
It is circling on the carousels.

The sky has become pinkish -
The sun bends to the sunset,
Dusk Garden lay on his shoulders -
So, the evening comes.

Following the first star
The month will be released.
Sun behind the village of the village,
The night came, around metlelo.

And in the crots until the morning
Fall asleep defense.

Remember, son, remember, daughter,
Day is a day and night.

Is it possible to split a day for four parts?

Sure you may! Let's talk about four pieces of day: morning, day, evening and nights.
In the morning the sun rises, it becomes a light sky, the clouds are pose, birds are waking up and chirped, the colors are revealed.
To formally impose this picture, listen to the poem "Morning rays",

The first beam fell to the bird,
On the pan-nurse.
She woke up: "Shadow-shadow-shadow,
Oh, what a wonderful day! "

The ray of the second fell on a bunny,
Introduced in the Namig oblique,
He picked up on the lawn
For Rosist grass.

The third ray beam, playing,
Woke chickens and geese.
He penetrated through the gap of the barn -
Immediately it was light in it!

On the piping upstairs
Wound a cockerel.
He was singing: "ka-ka-re-ku",
Raised scallop scallop.

The fourth raise raised bees.
They said: "Flower bloomed!"

The fifth beam penetrates me
Illuminated my bed
Ran through the wall
And whispered: "It's time to get up."

Let's remember what we do in the morning?

We wake up, wash and clean your teeth, make charging, breakfast.
After breakfast adults hurry to work, the older guys are to school, and the kids go to kindergarten or play at home, and then go for a walk.
The sun rises above, shines brighter, the day begins
The day is filled with studies, work. In the middle of the day, everyone sit down to lunch. After lunch, the kids are resting, and then walk again, play or engaged.
Gradually, the Sun is lowered below and below, and the silver-gray twilight is gluable. Comes evening. The moon appears in the sky and stars are lit.

What do we do in the evenings?

We are going to the whole family for dinner and evening tea, we share news, tell about what happened during the day. Someone reads a book or watching TV. In a word, in the evening everyone relaxed after a working day, and then go to bed.
Night comes to change the evening - the time of day, destined for sleep.

Listen to the lullaby song.

Steel aspen asna
Fall asleep, son, soon.

Maybe you will dream
Bright Fire Feather
Or scarlet flower.
Fall asleep soon, son!
In the dark sky, the month is shining,
Like flowers-seven-family.
Star Choir sings: "Bai-Bai!"
Sleep, son, fall asleep!

In winter, the night are long, and the days are short. In the summer, on the contrary, dark night hours less than bright daytime. And only in the days of equinox - September 23 and March 21 - days and nights are equal.

Listen to the poem "So much Light, how much darkness!"

There is a red maiden,
Carries not a driver in buckets.

Smiling itself:
In her buckets light and darkness.

We looked into the buckets we:
So much Light, how much darkness!

Questions and tasks:

1. How many hours in the days?
2. What two parts can you divide the day?
3. What four parts can you divide the day?
4. What time of day is the brightest?
5. What time of day is the darker?
6. Tell us about the morning, day, evening, night.
7. What is equinox?

The time of day for children, for adults and for all vegetable and wildlife consists of four segments of time: morning, day, evening and night. Every time interval differs from each other by the position of the Sun, the arrangement of the arrows on the clock, our affairs and classes.

So, in the morning we wake up, clean your teeth, breakfast and preparing for the day. In the afternoon we go to classes, we dine, do lessons and visit the circles. In the evening we play, rest, dinner and preparing to sleep. And at night we sleep sweetly.

(Some pictures on which the cursor handle appears, can be downloaded in a large size. To do this, click the mouse to the drawing to open a big picture for download)

Presentation for children: time of day

MORNING

In the villages from the very early morning, as soon as the sun rises the entire district wakes up a cockerel with his loud "ka-ka-re-ku"! And the alarm clock rings early in the city, saying that it's time to get up.

The time of day, when the sun is shown above the horizon, is called the morning that comes with a dawn. The sun only rises above the horizon, rises above the trees and roofs of the houses are higher and higher, gives us their bright rays and a sunny smile.

In winter, the morning begins later, and in the summer earlier. And in the summer, the morning Rosa happens on the grass. This is when the grass was wet, as if it was raining, and in fact there was no rain, just overnight the air was cooled and turned into small droplets of water, which donkeys on leaves and blades.

Morning begins with awakening. Plants wake up, revealing their buds, animals and birds wake up, crawling out of their minks and flying out of their nests. In the morning you need to get up from bed, carefully noted it. Then go wash, clean your teeth, make charging and gather in kindergarten or school. Meanwhile, in the kitchen in the morning, breakfast is already waiting for us.

DAY

Happy man is awake. Children play the courtyard at home or kindergarten, schoolchildren learn and after lessons are returned home, and adults work in the meantime. Little children in the afternoon should be a little sleep after dinner, and older schoolchildren make lessons to take up to the evening to do loved things and go for a walk.

In the afternoon, the sun climbs high into the sky and makes movement from East to the West in the sky, gradually dropping after dinner to the horizon. In the summer, the sun rises high above the horizon, and in winter it is low and quickly sits down.

In the daytime, the day for children undergo classes in kindergarten and at school, after which the lunch time comes. Lunch consists of first, second and third, after which you need to relax a little, and for children, a "quiet hour" is provided.

Closer to the evening the time comes to half one. The afternoon is a small dinner, which consists of a bowl of tea or fruit with juice, after which you can go for a walk.

EVENING

In the evening, the sun drops down and lower and lower and sits down the horizon. This time of the day is called the evening. And when the sun disappears behind the horizon you can observe a beautiful sunset. It can be bright in yellow-red rays. In winter, the evening comes early and the sun sits quickly, and in the summer, the evening is long and the sun sits slowly.

Plants, animals and birds are preparing to sleep. Flowers close their buds, animals climb into minks, an anthill in the forest closes, and birds sing lullared near their nests.

The evening is the time when children come from walking, and adults from work. This time dinner, after which you can play a little, watch TV or read an interesting book.

From the evening you need to prepare for tomorrow, gather clothes, books to school, clean your teeth and go to bed. After the evening, the darkest day is coming - the night.

NIGHT

At night, all people, animals and plants are resting to score forces the next day. People sleep in their beds under a warm blanket, dogs and cats are collapsed by eating on their cozy places, birds are hiding in the branches of trees, and the buds are closed in plants. Some animals, such as owls who sleep during the day, night awake, but most animals sleep at night in their nests and minks. Night is the time of silence, relaxation and sweet dreams.

The sun hides far behind the horizon and around very dark. But now in the sky you can see the stars and for some time the month comes out. In the afternoon of the star and the moon, it is unclear because of bright sunlight, but at night in full darkness they perform in all their glory.

At night, a month appears in the sky. This is the moon - our companion planet Earth. The month is full - they call the full moon. It happens in the form of a growing or decreasing crescent. And maybe not at all - the new moon is called. At that time, while we last night, the sun shines on another part of the globe and the day is going on.

Tasks playing for children about the time of day

Picture hours for children. Print and cut out a picture alarm clock. Carefully cut down the arrows, make a middle of the dial hole and attach the arrow on the clock throat. Now you can show that now an hour! And now: Morning, day or evening?

(Click the mouse to the drawing to open a big picture for download)

And here already ready-made clock with arrows in PSD format for Photoshop program - download clock with arrows (file in the clock.rar 518kb archive)

Watch with daylight pictures

(Click the mouse to the drawing to open a big picture)

Comparison of the duration of star (2) and solar (3) days with the coincidence of the directions of orbital and own rotation

The duration of the day on the planet depends on the angular velocity of its own rotation. In astronomy distinguish several types of day, depending on the reference system. If you choose a distant star as a point of reference point, then, unlike the central shining of the planetary system, such days will have a different duration. For example, on Earth there is a medium sunny day (24 hours) and star, or the Sideric Day (approximately 23 hours 56 minutes 4 seconds). They are not equal to each other, because because of the orbital movement of the Earth around the Sun, for an observer located on the surface of the earth, the sun shifts against the background of distant stars.

True sunny days are called a period of time between two upper climax (sequential passages of the center of the Sun through the southern part of the meridian (for the northern hemisphere); in other words, the time between two true noons); At the beginning of these days, the moment of passing the center of the Sun through the southern part of the Meridian; The hour angle of the center of the Sun is called true time (see equation of time). True sunny day is longer than the star day and their duration changes during the year, which comes from the inclination of the ecliptic to the plane of the equator and from the uneven movement of the Earth near the Sun.

International Unit System (SI)

Unit of time measurement (Russian designation: day; international: D) refers to the number of non-system units of measurement and in si is not included. However, in the Russian Federation, it is allowed to use without limitation with the scope of application "All areas". In this case, 1 day is taken equal to exactly 86,400 seconds. In a second, the second is defined as 9 192,631,770 periods of radiation, corresponding to the transition between two ultra-thin levels of the main state of the Cesium-133 atom. Accordingly, 794,184,928,000 such periods can be considered to determine the day in SI.

In Astronomy, the day, determined after a second C, are called Julian days.

In the average sunny days, there is no whole number of seconds (for example, their duration on the era of 2000.0 was 86400.002 (c), and the duration of the average sunny day is also inconsistent due to the age-old change in the angular velocity of the Earth's rotation (see).

Cultural borders of the day

For most day animals, the day naturally begins at dawn and ends at sunset. A person, with his cultural traditions and scientific knowledge, formed his own ideas about the time of the beginning of the day and division them to the characteristic periods.

Ancient man focused on time for a day or night. The earliest mention of the day as connected together and night is found in Homer, while the day in his works began with dawn. In ancient Russia until the XIII century "day", as a unit of time bills did not use. Old Russian chroniclers considered time from dawn to dawn.

• 0 hours: 19-24 hour belts;
• 6 hours: 13-18 hour belts;
• 12 hours: 7-12 hour belts;
• 18 hours: 1-6 hour zones.

Thus, for example, in European countries, meteorological days begin at 18:00 (UTC) - at this time the results of the day are summed up, the average and extreme air temperature and other meteoparameters are calculated. If the 1st time zone in the list presented is the UTC + 1 belt, we get that meteorological days in a particular place can begin in the range from 19:00 to 24:00 at the official local time. In Russia, the time of several time zones is applied, so for each region there is its own border of meteorological days (UTC time).

Special agreements related to days

The validity period of temporary pass and so on. It may end up at midnight. However, if the replaceable service provider's schedule (for example, public transport) covers, for example, the interval of 6:00 day to 1:00 the next night (which can also be marked as 25:00), then the last hour can be legalized as part previous day. For example, the period of action of monthly travel tickets in a city bus or trolleybus in Russia at the occurrence of the 1st day of the next month does not expire until the end of the work shift personnel of public transport, if its start fell on the previous day. For Nederlandse Spoorwegen (Dutch Railways) Daily ticket is valid 28 hours, from 0:00 to 28:00 (i.e., 4:00 next day). The term of bandwidth tickets "London Regional Transport" (London Public Transport) expires at 4:30 next day after the date of their activation.

Division of day

The number of parts for which the day shared, or separately night and day depended on the degree of development of this people and increased gradually with the development of mankind. Most of the peoples of the new world divided the day only for four parts, corresponding to the sunrise, the highest point of the day of his day, the sunset and, finally, the middle of the night. According to the testimony of the Traveler Gorbowou, who described Iceland in the middle of the XVIII century, Icelanders shared the day at 10 parts. The Arabs distinguished only the sunrise, rise and lower it, the sunset, twilight, night, the first cry of the rooster and dawn. However, some, in the past of uncivilized peoples, it was possible to find a relatively accurate division of the day, such as the natives of the societies of the society, which during Cook had a division of the day at 18 parts, whose length was neodynakova; The shortest intervals corresponded to the morning and the evening, the longest - midnight and noon.

In Babylon, there was also division of the day and night to 12 hours. According to the "History" (II, 109) of Herodotus, from Babylonians this system was adopted by the Greeks, later, probably from Egyptians or Greeks, learned the Romans. For example, in winter, the duration of the "day hour" in Rome was about 45 minutes.

Old Russian daily calculus

Period	Number of day watches	The beginning of the first hour of the day on the modern calculation	Number of night watch	Start of the first hour of the night according to the modern calculation
November 27 - January 1	7	8:30	17	15:30
January 2-16; November 11-26.	8	7:21	16	15:21
January 17 - February 1; October 26 - November 10	9	7:30	15	16:30
February 2-17; October 10-25	10	6:21	14	16:21
February 18 - March 5; September 24 - October 9	11	6:30	13	17:30
March 6-20; September 8-23	12	5:21	12	17:21
March 21 - April 5; August 23 - September 7	13	5:30	11	18:30
April 6-22; August 7-22	14	4:21	10	18:21
April 23 - May 8; July 23 - August 6	15	4:30	9	19:30
May 9-24; July 6-22	16	3:21	8	19:21
May 25 - July 5	17	3:30	7	20:30

Division at 12 main parts

Traditional chinese daily calculus

Times of Day	Name	Name value
23:00-01:00	Rat hour	Time when rats are most active in search of food. Rats also have a different amount of fingers on the front and hind legs, so that these rodents have become a symbol of "reversal", "new start".
01:00-03:00	Hour bull	The time when the wheels begin to chew a cheer, slowly and with pleasure.
03:00-05:00	Hour tiger	Time when Tigers are the most fierce, fishing in search of mining.
05:00-07:00	Hour rabbit	Time when a fabulous jade rabbit on the moon prepares vegetable elixirs to help people.
07:00-09:00	Dragon Hour	Time when the dragons hill in the sky to go rain.
09:00-11:00	Snake hour	Time when snakes leave their refuge.
11:00-13:00	Horses hour	The time when the sun is high in the zenith, and then like other animals lay for a holiday, the horse is still on the legs.
13:00-15:00	Sheep hour	Time when sheep and goats eat grass and often routine.
15:00-17:00	Monkey hour	Time Active Life Monkey
17:00-19:00	Petush hour	Time when roosters begin to gather in their communities.
19:00-21:00	Hour dog	Time dogs to fulfill their duties on building buildings.
21:00-23:00	Pig hour	The time when the pig is serenely sleep.

Division on 30 main parts

Division on 22 main parts

Division on 10 main parts

Time	Geological period	Number of days a year	Length day
Today	Quaternary	365	24 hours
100 million years ago	Yura	380	23 hours
200 million years ago	Permian	390	22.5 hours
300 million years ago	Carbon	400	22 hours
400 million years ago	Silicon	410	21.5 hours
500 million years ago	Cambrian	425	20.5 hours

To find out the duration of the day before the era of the appearance of corals, scientists had to resort to the help of cinema algae. Since 1998, Chinese researchers Zhu Schisin, Juan Pupuan and Xin Houghjan from analyzed more than 500 fossil stromatolites with age 1.3 billion years old, the ever near the equator and buried on the mountains of Yanshhan. The cinema algae respond to the shift of the light and dark time of the day the direction of its growth and color depth: in the afternoon they are painted in bright colors and grow vertically, at night they have a dark color and grow horizontally. According to the appearance of these organisms, given the speed of their growth and accumulated scientific data on geology and climatology, it turned out to be possible to determine the annual, monthly and daily rhythms of growth of synephae algae. According to the results obtained, scientists were concluded that 1.3 billion years ago (in the Precambrian era) lasted the earthly day 14.91-16.05 hours, and the year consisted of 546-588 days.

There are opponents of this assessment, indicating that these studies of ancient tidal sediments, Tydalitov, contradict it.

Changing the duration of the day from 1974 to 2015 (vertically - scale in milliseconds)

In addition to changing the speed of rotation of the Earth at a long period of time (and flowing from here a change in the duration of the day), insignificant changes in the speed of rotation of the planet occur, associated with the mass distribution, for example, due to the reduction of the volume of the world ocean or the atmosphere from the fluctuations of their average temperature . When cooling the world's ocean or atmosphere, the Earth rotates faster (and vice versa), since as a result there is a law of preserving the moment of momentum. Also, the change in the average duration of the day can cause geological events, such as strong earthquakes. Thus, as a result of the 2004 earthquake in the Indian Ocean, the duration of the day decreased by about 2.68 microseconds. Such changes are marked and can be measured by modern methods.

In 1967, the International Committee of Measures and Libra accepted a fixed second, without binding to the current duration of the sunny day on Earth. The new second was equal to 9,192,631,770 radiation periods corresponding to the transition between two ultra-thin levels of the main state of the cesium-133 atom in the absence of perturbation by external fields. Coordination of the Wide Coordinated Time Scale UTC (based on a uniform atomic time scale) with a changing duration of the day is made using

Did any adult can determine what day is? If you think about it, then this word we often call only the time when awake, equating them to the day. But it is incorrect. To disassemble once and for all in this matter, it will take quite a bit of time.

What is the directory and dictionary talk about this?

If you look into them, then several interpretations of this word will be found. And the first answer to the question what a day is such a definition: a time countdown unit, which is equal to the approximate value of the planet's conversion period around the axis. Why approximate? Because it is not even, but has moments and even seconds. To be accurate, then 23 hours 56 minutes 4 seconds. It is impossible to divide them on a smooth number of parts. Yes, and up to 24 hours is not enough a little bit.

But this theory is not crucial. It turns out, a day can be sunny and star, planetary and used in civilian life.

In order to determine what a day is, you will need to choose any time and count 24 hours from it. Usually the bill of day begins with sunrise, although it is more convenient to count from midnight. That is, from that hour when a new calendar day begins.

How is the division of the day?

First, on 24 equal parts. From here, it is logical about the answer to the question: it is 24. Each of them consists of 60 minutes. So, in total in days of 1440 minutes. But this is not all, the latter are divided for seconds. Their number is equal to 86,400.

Secondly, there is another concept as time of day. In other words, morning, day, evening and night. Here the division is not so definitely as in the previous paragraph. This is due to the subjective perception of the day by each person and different peoples. Yes, and technical development erased the boundaries between the concepts of "Morning" and "Day". If earlier morning came with the sunrise, because only then it was possible to start working on the street, now with the use of artificial lighting of the streets to work in the fresh air at least at least at night.

Nevertheless, technical progress and the ability to communicate with people of different countries demanded to introduce a single division. Therefore, the time of day by the clock was like this:

• from midnight to 6 o'clock - night;
• following six hours - morning;
• 6 hours after noon - day;
• last six hours - evening.

What divisions of the day were in the past?

Arab peoples, for example, allocated such moments of the day of the day:

• dawn;
• sunrise;
• time of his movement in the sky;
• approach;
• dusk;
• time when there is no sun on the sky, that is, the night.

The next in the days is dawn, the other name is dawn. He precedes the sunrise. That is, during him there is already a light, but the sun is still hidden behind the horizon.

The third period is the sunrise. It is associated with the direct appearance of the shone on the sky.

The climax of the sun movement is associated with the next time of the day - noon. Closer in the evening the time comes, which is called "Walling". By analogy with the term "dim" is the gap, when it is still light.

The sunset is associated with time when the sun is hidden behind the horizon. Immediately after the sunset, it comes to death, which is called twilight.

And what's larger than a day?

It is logical that the week, month and year. Therefore, after solving the issue, what a day will want to understand and with the definitions of other time units.

The smallest of them is a week. It consists of seven days. The calendar is counted from Monday and ends with Sundays. But it can be any sequence of seven days after each other.

Some larger month. It contains from 28 to 31 days. The difference in this amount depends on the misunderstanding value of the lunar month, which is a little more than twenty-eight days. Initially, the number of days in months was alternated and it was 30, then 31. And one, the last year - February - turned out to be the shortest. It was 29 days. But with the times there were small changes. One of the months - July - was called in honor of Julia Caesar (this month the emperor was born). AUGUST came to replace the ruler. By the decision of the emperor, one of the summer months began to wear his name. The number of days in it was also changed to 31. To take it was decided at the month, which is so shortest. So, February became another one for a day.

The largest unit of time in the calendar was the year. And he also turned out to be not an integer. Therefore, its value ranges from 365 to 366. The first value is taken for ordinary years, and the second corresponds to the leap. The second make it possible to become somewhat longer. Namely exactly for a day.

Hello! I have a few questions united by one topic. The church day begins in the evening. According to one sources in 17h. On the other 18h., "Grandma" generally speak after sunset, how is it right? Based on this, please help, how to calculate the days of posts and holidays. For example: 1) Post medium - from evening to evening or from 00h. up to 24h. Wednesdays or from Evening Tuesday up to 24 hours. Environments? 2) Multi-day posts end on the eve or 24 hours.? 3) How to calculate Sundays and holidays to read the paths. In the evening (on the eve) + in the morning or once again in the evening? 3) The saddemic begins with Sunday she also "week", if I understand correctly, or from Monday. those. If there is an indication to read prayers all the week, then it is up to Saturday or Sunday evening? For previously thanks for the answer! Vladimir.

Replies Archpriest Alexander Ilyashenko:

Hello, Vladimir!

Indeed, the church day begins in the evening, more precisely, from the evening worship, which already applies to the next day. There is no accurate "hour" in this case, because in some temples, the evening worship begins from 17 o'clock, in other temples - from 18, thirdly - from 16 ... At the same time, all posts start from 00.00 hours and end at 24.00 hours. That is, we will post me not from the evening of Tuesday, and from 00.00 hours of the medium. Multi-day posts ends at 24.00 hours. However, multi-day posts ends with a festive liturgy, and it is accepted for the meal only at the end of the liturgy, even if you are not incident on this day for some reasons.
The trails can be read from the evening on the eve of the holiday - after all, they are already reading and walk in the temple during the evening worship.
The saddemic begins from Monday. So, the first week of the Great Post begins not for a farewell Sunday, but on Monday after him. As for prayers, there may be options - so, the submissive prayer of Ephraim Syrina, added to the morning and evening prayers, is read from the evening of Sunday and until the morning Friday (on Saturday, the stakes are not performed, and therefore this prayer is not read) , and Easter hours, instead of the morning and evening prayers, we read from the day of Easter (Sunday) and until the morning Saturday is bright weeks. If you are not sure how to read a particular prayer, ask a question to the priest.

Sincerely, Archpriest Alexander Ilyashenko.