Can every adult define what a day is? If you think about it, we often call this word only the time when we are awake, equating them to the day. But this is not true. It will take quite a bit of time to sort out this issue once and for all.
What do the handbook and dictionary say about this?
If you look into them, you will find several interpretations of this word. And the first of the answers to the question of what a day is, is such a definition: a unit of time reference, which is equal to the approximate value of the period of rotation of the planet Earth around its axis. Why approximate? Because it is not even, but has minutes and even seconds. To be precise, 23 hours 56 minutes 4 seconds. Dividing them into an even number of parts does not work. Yes, and up to 24 hours is not enough just a little bit.
But the theory doesn't stop there. It turns out that the day can be solar and stellar, planetary and used in civilian life.
In order to determine what a day is, you need to choose any point in time and count 24 hours from it. The day usually starts at sunrise. Sun, although it is more convenient to count from midnight. That is, from the hour when a new calendar day begins.
How is the day divided?
First, into 24 equal parts. This logically leads to the answer to the question: how many hours are there in a day? Exactly 24. Each of them consists of 60 minutes. So there are 1440 minutes in a day. But that's not all, the latter are divided into seconds. Their number turns out to be 86,400.
Secondly, there is such a thing as the time of day. In other words, morning, afternoon, evening and night. Here the division is no longer as clear-cut as in the previous paragraph. This is due to the subjective perception of the day by each person and different nations. Yes, and technical development erased the boundaries between the concepts of "morning" and "day". If earlier morning came with sunrise, because only then it was possible to start working on the street, now with the use of artificial street lighting it is possible to work outdoors even at night.
And yet, technological progress and the ability to communicate with people from different countries demanded a single division. Therefore, the time of day by the clock became this:
- from midnight to 6 o'clock - night;
- next six hours - morning;
- 6 pm - day;
- last six hours - evening.
What divisions of the day were there in the past?
Arab peoples, for example, singled out such moments in the development of the day:
- dawn;
- sunrise;
- the time of its movement across the sky;
- entry;
- twilight;
- the time when the sun is not in the sky, that is, the night.
But the natives of the Society Islands at the time when Cook discovered them, divided the day into 18 intervals. And each of them was different in duration. The shortest parts of the day were morning and evening. The longest duration was at midnight and noon.
What words exist in Russian to determine the time of day?
In addition to the generally accepted large segments, such as morning with afternoon and evening with night, there are even smaller ones. Moreover, they are given their own names.
The first of these concepts is "dark". That is, the time when it is still or already dark. This happens just before dawn, and also just after sunset.
The next day is dawn, its other name is dawn. It precedes the sunrise. That is, it is already getting light during it, but the sun is still hidden behind the horizon.
The third period is sunrise. It is associated with the direct appearance of the luminary in the sky.
The culmination of the movement of the sun is associated with the next time of day - noon. Toward evening, the time comes, which is commonly called "darkness". By analogy with the term "dark", this is the period when it is still light.
Sunset is associated with the time when the sun disappears below the horizon. Immediately after sunset, semi-darkness sets in, which is commonly called twilight.
What is larger than a day?
It is logical that the week, month and year. So after decidingthe question of what a day is, you will want to understand the definitions of other units of time.
The smallest of them is a week. It consists of seven days. The calendar is counted from Monday and ends on Sunday. But it can be any sequence of seven consecutive days.
Slightly larger month. It contains from 28 to 31 days. The difference in this number depends on the non-integer value of the lunar month, which is slightly more than twenty-eight days. Initially, the number of days in the months alternated and was either 30 or 31. And one, the last of the year - February - turned out to be the shortest. It had 29 days. But little has changed over time. One of the months - July - was named after Julius Caesar (the emperor was born in this month). August replaced the ruler. By the decision of the emperor, one of the summer months began to bear his name. The number of days in it was also changed to 31. It was decided to take it from that month, which is already the shortest. So, February has become another day less.
The largest unit of time in the calendar is the year. And he, too, was not a whole number. Therefore, its value ranges from 365 to 366. The first value is taken for simple years, and the second corresponds to leap years. The latter make it possible for February to become somewhat longer. Namely, exactly for a day.
