4 года назад
• Вы подписаны
By processing seismograms of nuclear tests at the turn of the 1970s, scientists have shown that the rotation period of the Earth's inner core changes cyclically. All cosmic bodies rotate around their axis. The solid bodies to which our Earth belongs rotate as a whole and, as a rule, very evenly. Therefore, a second, previously defined as one 86400 th fraction of an Earth day, has long served as a standard unit of time. At any point on the Earth's surface, the result of its measurement will be the same...
