Theingi Mg Mg-Me and my stress free days Photos

Theingi Mg Mg-Me and my stress free days Photos

Theingi Mg Mg-Me and my stress free days Photos

Theingi Mg Mg-Me and my stress free days Photos

Theingi Mg Mg-Me and my stress free days Photos

Myanmar Model-Theingi Mg Mg

A day is approximately the period of time during which the Earth completes one rotation around its axis.[1] A solar day is the length of time which elapses between the Sun reaching its highest point in the sky two consecutive times.[2]

In 1960, the second was redefined in terms of the orbital motion of the Earth in year 1900, and was designated the SI base unit of time. The unit of measurement “day”, was redefined as 86,400 SI seconds and symbolized d. In 1967, the second and so the day were redefined by atomic electron transition.[3] A civil day is usually 86,400 seconds, plus or minus a possible leap second in Coordinated Universal Time (UTC), and occasionally plus or minus an hour in those locations that change from or to daylight saving time.[2][1]

Day can be defined as each of the twenty-four-hour periods, reckoned from one midnight to the next, into which a week, month, or year is divided, and corresponding to a rotation of the earth on its axis.[4] However, its use depends on its context; for example, when people say ‘day and night’, ‘day’ will have a different meaning: the interval of light between two successive nights, the time between sunrise and sunset;[5] the time of light between one night and the next.[6] However, in order to be clear when using ‘day’ in that sense, “daytime” should be used to distinguish it from “day” referring to a 24-hour period;[7] this is since daytime usually means ‘the time of the day between sunrise and sunset.[8] The word day may also refer to a day of the week or to a calendar date, as in answer to the question, “On which day?” The life patterns (circadian rhythms) of humans and many other species are related to Earth’s solar day and the day-night cycle.

Several definitions of this universal human concept are used according to context, need and convenience. Besides the day of 24 hours (86 400 seconds), the word day is used for several different spans of time based on the rotation of the Earth around its axis. An important one is the solar day, defined as the time it takes for the Sun to return to its culmination point (its highest point in the sky). Because celestial orbits are not perfectly circular, and thus objects travel at different speeds at various positions in their orbit, a solar day is not the same length of time throughout the orbital year. Because the Earth orbits the Sun elliptically as the Earth spins on an inclined axis, this period can be up to 7.9 seconds more than (or less than) 24 hours. In recent decades, the average length of a solar day on Earth has been about 86 400.002 seconds[9] (24.000 000 6 hours) and there are 365.242199074 solar days in one mean tropical year.

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