What is the time of 24 hours?

Time: In the applied Gregorian calendar, due to the discovery of the inconsistency of universal time in various places, therefore, in 1879, the Canadian railway engineer Vullemon proposed the concept of "zone time", which was endorsed at an international conference in 1884, thus formally establishing the "zone time system" that unified the world's measurement time. The "zone time system" states that every 15° longitude range on Earth is a time zone (i.e., the longitude that the Sun travels in one hour).

In this way, the entire surface of the Earth is divided into 24 time zones. The "** meridian" of each time zone is specified as 0° (i.e., "prime meridian"), 15° east and west, 30° east and west, and 45° east and west longitude......Up to the 180° meridian, all points within the range on the east and west sides of each **meridian are used as the standard time.

This division of world time zones is based on the prime meridian. The interval from west diameter to east longitude is 15°). The two boundaries of the zero time zone are respectively east and west, and a time zone is drawn every 15 degrees of longitude, and 12 time zones are drawn each from the east and west, and the 12th time zone in the east and 12 time zones in the west coincideThe world is divided into 24 time zones.

Each time zone uses the mean solar time of the ** meridian as the standard time of the zone.

The "zone time system" largely solves the confusion of time in different places, so that there are only 24 different times in the world, and because the time difference between adjacent time zones is exactly 1 hour, it is extremely easy to convert the time between different time zones. As a result, this zonal time system has been used around the world for 100 years.

There is also a problem with the zonal time system: if you travel the world from west to east, every time you cross a time zone, you will move your watch forward by an hour, so that when you cross 24 time zones and return to the same place, your watch will also be set forward exactly 24 hours, which is the same hour the next day;Conversely, when you travel the world from east to west, your watch indicates the same hour of the previous day. In order to avoid this phenomenon of "date confusion", the 180° meridian is uniformly defined as the "International Date Change Line".

When you cross the International Date Line from west to east, you must subtract one day from your timing systemConversely, if you cross the International Date Line from east to west, you must add a day.

Because there are only 24 hours in a day.

The Earth is supposed to be ten hours a day, but due to the gravitational pull of the Moon, the Earth rotates slowly. It became 24 hours, and now, thanks to the Moon, the Earth is still reducing seconds every day.

My understanding is this: from the beginning of an event to the end of the event, it is done in exactly 24 hours, that is, from 0 hours, 0 seconds to 23 hours and 59 seconds.

Do something in one day.

Morning: 0:00 — before sunrise (because the sunrise varies depending on the season) Morning: Sunrise — 9 o'clock.

Morning: 9 a.m. – 11 a.m.

Noon (also known as noon): 11 a.m. - 1 p.m.

Afternoon (including noon): 12 p.m. – sunset.

Evening: 5:30-7:30

Evening: No subdivision is after sunset - 12:00, subdivision is considered evening.