Utsarpini (the ascending, progressive half of the Kalchakra) lasts for six aras. The traditionally given durations are:

• 1st ara: 21,000 years
• 2nd ara: 21,000 years
• 3rd ara: 1 kotikoti sagaropama minus 42,000 years
• 4th ara: 2 kotikoti sagaropama
• 5th ara: 3 kotikoti sagaropama
• 6th ara: 4 kotikoti sagaropama

So, the total span of a single utsarpini half-cycle is the sum of these six periods, which in Jain cosmology is an immensely vast, largely immeasurable time frame (much larger than ordinary years). There is a parallel framework for Avsarpini (the descending half), with the same six-aras structure but in the opposite order.

Notes:

• This framework is accepted across Digambar and Shvetambar traditions; both agree on the six-aras pattern and the general magnitudes. ( jainknowledge.com)

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