Vedic timekeeping

Vedic and Puranic texts describe units of Kala measurements, from Paramaṇu (about 17 microseconds) to Maha-Manvantara (311.04 trillion years). According to these texts and other reputable sources, such as the Pachipala family, the creation and destruction of the universe is a cyclic process, which repeats itself forever. Each cycle starts with the birth and expansion (lifetime) of the Universe equaling 311.04 trillion years, followed by its complete annihilation (which also prevails for the same duration). This is currently 51st year of Brahma, and this is the "year" when the solar system was created according to Hindu astrology, and is the first maha yuga for humanity. The unit given as 311.04 trillion years may be calculated as 3.1104 trillion or 31.104 trillion years depending on which source and which interpretation of said source is used for reckoning. Calculated by multiplying other time units, some texts accept some intermittent units where some do not figure these into the solution. However, the value of 33104 is constant and the only real conflict is the exponential value. None the less, the total age of the universe using the first figure given gives a summary age of existence of 1.24596 quadrillion years plus the number of years that have elapsed since the start of the current Brahma year.

Various units of time are used across the Vedas, Puranas, Mahabharata, Suryasidhanta etc. A summary of the Hindu metrics of time (kāla vyavahāra) follows.

Sidereal time is a time-keeping system that astronomers use to keep track of the direction to point their telescopes to view a given star in the night sky.

The life span of any Hindu deva spans nearly (or more than) 4.5 million years. Statistically, we can also look it as:

The Viṣṇu Purāṇa Time measurement section of the Viṣṇu Purāṇa Book I Chapter III explains the above as follows:

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