How Time was divided... ?

The oldest known observations on "TIME" and it's division was first found in Vedic Cosmology dating back to late 2nd millennium  BCE. Aryabhatta gave his great contribution to mankind on making the human race to understand what is time and how it was classified ...This classification was truly adopted and practiced with complete scientific proofs and evidences.

The division of time is as follows :
According to Vedic Cosmology  and surya sidhantha (Science involved on study of stars and sun)the universe is cyclically created and destroyed.Where it was classified on basis of Bramha's Life span.According to Hinduism Brahma is god of creation.One day of Bramha's life is Known as kalpa.
1 kalpa = 14 manvantras + 6 mahayugas = (appox) to 1000 yugas.
Manvantra is the collection of 71 mahayugas i.e 1 Manvantra = 71 mahayugas.
Maha yuga is collection of 43,20,000 human years.

One Maha yuga is collection of 4 yugas ...
Kruth yuga ,Tretayuga, Dwapara yuga  and Kali yuga.
1 Kruth yuga = 17,28,000 human years
1 Tretayuga = 12,96,000 human years
1 Dwapara yuga = 8,64,000 human years
1 Kali yuga = 4,32,000 human years

14 manvantra = 14 x 71 mahayugas = 994 mahayugas
994 mahayugas + 6 mahayugas = 1000 yugas

After completion of  one Kalpa the Universe gets destroyed and recreated forming or transforming into new realms.That the reason why the Universe is said to be expanding....The cycle goes on for 100 'divine years' at the end of which Bramha perishes and is regenerated. Bramha's entire life equals 311 trillion, 40 billion years. Once Bramha dies there is an equal period of unmanifestation for 311 trillion, 40 billion years, until the next Bramha is created.
Since till now we were dealing with the time in large scape ... this time is simplified into year -(collection of 12 months),month - (consists of two pakshas) , Paksham (consists of 15 days one is called as krishna paksham ends with a new moon and the other is shukla paksham ends with full moon) later into a day with 23 hr and 54 min 08 seconds - first calculated by arya bhatta. then in hours,minutes,seconds.

Seconds were first classified since this was discussed in Vedas - featured as Anu sidhanta.

Asians were first to determine  length and breadth of time, religions like Hinduism,Buddhism,Judaism  were first to analyze the concepts of time scientifically.They were first to generalize and justified the facts using sciences like astronomy,cosmology,topography leaving away results with high accuracy comparable to latest ones.