Thanks for these details, Akhl. I used to wonder which yugas there were, and how many, and now I know.Thanks, Rajnish.
One cycle of the four yugas (Satys, Treta, Dwapar, Kali) is called as one divya yuga or one maha yuga.In one day of Lord Brahma, there are 1000 divya yugas. The night of Lord Brahma is of the same duration.The durations of various yugas in Earth years are as follows:-Satya yuga - 1728000Treta yuga - 1296000Dwapar yuga - 864000Kali yuga - 432000__________________Total - 4320000Thus 1 divya yuga = 4320000 Earth years = 4.32 million Earth years. Note that in Puranas 1 year means 360 (and not 365 or 366) day-nights.For gods(i.e. in heaven), 1 year =360 Earth years. Therefore, in god years, we can calculate the durations of the yugas by dividing the durations in Earth years by 360.Thus, for gods:-Satya yuga - 4800Treta yuga - 3600Dwapar yuga - 2400Kali yuga - 1200__________________Total - 12000Thus 1 divya yuga = 12000 god-years
One question I have - are 'years' as described in the scriptures and epics the same as what we understand today, even if they had 360 rather than 365 days? The above describes the earth being ~4 million years old, but are these numbers supposed to be literal and mathematically accurate measures of when and how long things lasted, or are they more figurative and metaphorical, indicating a long time, and the actual numbers providing more of a relative comparison between different eras? Generally, human life spans are known to have grown, not shrunk over the ages, which is why I tend to think of such numbers as being more figurative rather than literally accurate figures.
Like Rama's reign is supposed to have lasted 10000 or 11000 years, depending on what one's read, but if one looks at recent theories about him being born in 5174BC, then by that theory, he should still be ruling us ❓ And it's not just time that seems to be measured differently - even head counts of people, soldiers, sizes of armies, et al would lead one to think that the earth (more precisely, Aryavarta) had some hundreds of billions, if not trillions, inhabiting it.
One example: when Bharat was sent by Rama to conquer Gandhara (7:100-101), he is described as using the kaalastra (same as yamastra?) to wipe out 30 million Gandharvas in a moment. Doesn't that sound like a hugh figure - even the most high magnitude H-bombs wouldn't do that much damage. So when numbers like these are tossed about, do you think it's more metaphorical and figurative to describe the magnitude of a damage, rather than an attempt to accurately quantify it?