Maha Yuga

The astronomical time cycles mentioned in ancient Hindu astronomical and Puranic texts are remarkably similar to each other. Old Indian measures are still in use today, primarily for religious purposes in Hinduism and Jainism. They also are employed in the teachings of Surat Shabda Yoga.The Hindu cosmological time cycles are described in verses 11–23 of Chapter 1, Surya Siddhanta  : "(Verse 11). That which begins with respirations (prāna) is called real; that which begins with atoms(truti) is unreal. Six respirations make a vinādi, sixty of these a nādi. (12). And sixty nādis make a sidereal day and night. Of thirty of these sidereal days is composed a month; a civil (sāvana) month consists of as many sunrises. (13). A lunar month, of as many lunar days (tithi); a solar (sāura) month is determined by the entrance of the sun into a sign of the zodiac; twelve months make a year. This is called a day of the gods. (14). The day and night of the gods and of the demons are mutually opposed to one another. Six times sixty of them are a year of the gods, and likewise of the demons. (15). Twelve thousand of these divine years are denominated a Quadruple Age(caturyuga); of ten thousand times four hundred and thirty-two solar years (16) is composed that Quadruple Age(caturyuga), with its dawn and twilight. The difference of the Golden (krtayuga) and the other Ages (yugas), as measured by the difference in the number of the feet of Virtue in each, is as follows : (17). The tenth part of a (Quadruple) Age (caturyuga), multiplied successively by four, three, two, and one, gives the length of the Golden (krta) and the other yugas: the sixth part of each belongs to its dawn and twilight. (18). One and seventy caturyugas make a Patriarchate (manvantara or Patriarchal Age of one manu); at its end is a twilight which has the number of years of a Golden Age (krtayuga), and which is a deluge (pralaya). (19). In an Aeon (kalpa) are reckoned fourteen such Patriarchs (manus) with their respective twilights; at the commencement of the Aeon (kalpa) is a fifteenth dawn, having the length of a Golden Age (krtayuga).(20). The kalpa, thus composed of a thousand caturyugas, and which brings about the destruction of all that exist (bhoo), is a day of Brahma; his night is of the same length. (21). His extreme age is a hundred, according to this valuation of a day and a night. The half of his life is past; of the remainder, this is the first kalpa. (22). And of this kalpa, six Patriarchs (manus) are past, with their respective twilights; and of the Patriarch Manu son of Vivasvant, twenty-seven Ages (caturyugas) are past; (23). Of the present, the twenty-eighth, Age (caturyuga), this Golden Age (krtayuga) is past; from this point,reckoning up the time, one should compute together the whole number."
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