Kalpa

Vishnu Purana states the following.  Four ages (4.32 Million Years = One Maha Yuga = four Yugas, BG08 ) are the lifetime of some celestial beings; some live for the duration of the of a Manu (308,571,429 years); you (Dhruva) will live for the duration of a Kalpa (4.32 billion years).

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