Avasarpini, the descending (degenerative) half of the Jain time-cycle, lasts an extremely long duration. In Jain cosmology, the entire avasarpiṇī is said to be 10 crore crore (i.e., 100 trillion) sāgaropama years. Within that half-cycle, there are six aras; the current era we are in is the 5th ara (the Dukhama/Ḍhuksama phase) of Avasarpini, which lasts 21,000 years. We are currently still within that 5th ara. Some traditional calculations place Mahavira’s nirvana at the end of the 4th ara, about 2,551 years ago (as of 2024 CE). ( jainknowledge.com)

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