Yugas and Mahayugas

Traditionally the epic Ramayana belongs to Treta Yuga and date as far as back as 888,000 years in the past. 

There are four yugas.

Satya or Krita Yuga-1, 728,000 years

Treta Yuga-1, 296,000 years

Dwapara Yuga-864, 000 years

Kali yuga-432, 000 years

One cycle of all yugas is called Mahayugas.

1000 Mahayugas is equal to one day of Brahma (4,320,000 or 4.32 billion human years), which is the actual scientifically estimated age of our Sun.

Each day of Brahma is divided into 14 manvantara periods.

Each manvantara is lasting 71 Yuga cycles.

We are now in vaivasvatha manvanthara which is the seventh manvantara

According to the “Surya Siddhant” the ‘Kaliyug” started on the afternoon of February 3102 BC

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1. The major alteration in the fact of the story found in the Adhyatma Ramayana is the introduction of a "Maya Sita" or Shadow Sita throughout the period of her abduction. The (real) Sita disappears into the fire just before the golden deer episode. Tulasidasa also follows the Adhyatma Ramayana in this respect. In the Adhyatma Ramayana, Sita emerges from the fire at the end of the war when the shadow Sita enters into it. (The whole drama is preplanned and enacted at the bidding of Sri Rama Himself).
2. Other alterations in the Adhyatma Ramayana include: Ravana treats Sita with the respect due to a mother and Sri Rama establishes a Shiva Lingam at the site of the bridge to Lanka.
3. The major contribution of the Adhyatma Ramayana lies in the casting of Rama in the role of the spiritual teacher and in the several exquisite hymns sung in praise of Rama. There are four occasions when Rama assumes the role of the teacher and gives philosophical disquisition.
4. Rama reveals himself as four-handed Mahavishnu at his very birth, a feature that is not seen in Valmiki
5. Sage Valmiki depicts Sri. Rama as an ideal man while admitting his divinity, whereas Sage Vyasa present him as the Supreme Being incarnate with the full remembrance of his divinity and the recognition of it by all wise men.
6. In response to Lakshmana’s questions on different occasions he teaches the knowledge, devotion and detachment, methods of worship and the way of emancipation. In reply to Kaushalya’s query, Rama teaches the three Yogas of Karma (action), Jnana (knowledge) and Bhakti (devotion).
7. The well-known Ramagita is part of Adhyatma Ramayana. It contains teachings on Advaita Vedanta. The real contribution of this work is in its repeatedly propounding the doctrine that Rama is Brahman the absolute and that Sita is His Maya-shakti or Prakriti, thereby raising the personality of Rama to the highest level and providing a firm base to the worship of Rama.
8. Ahalya the wife of Sage Gautama Maharishi is in the invisible form in the Valmiki Ramayana, whereas in the Adhyatma she has been depicted in the rock formations.
9. In the Ayodhya Kanda of Adhyatma Ramayana the section opens with a visit of Sage Narada to Rama to remind him of the purpose of his incarnation, which Sri. Rama acknowledges. All these incidents are not in Valmiki.
10. In the Adhyatma, banishment of Sri Rama is accomplished by the Devas through Goddess Saraswathi, by possessing the two women i.e. maidservant Manthara and Kaikeyi. In Valmiki, this incident is explained as a simple court intrigue.
11. Sage Valmiki's evil past has been explained in detail in Adhyatma, but not in the other.
12. In Adhyatma, Lakshmana requests Rama to instruct him on the means of attaining moksha. Rama also gives him an elaborate discourse on Jnana and Bhakti, conveying the quintessence of Vedanta. This is not in Valmiki's.
13. According to Adhyatma, Ravana is aware that Sri Rama in human form is Lord Vishnu incarnated to kill him. Ravana is also aware that destruction at Sri Rama's hand is an easier way of gaining moksha than through spiritual practices (devotion through confrontation - an example for Vidvesha Bhakti).
14. In Adhyatma - unknown to Lakshmana, Rama informs Sita that Ravana will be coming to abduct her and that therefore he is handing her over to the Fire deity Agni for safe custody, till he takes her back again. In her place Maya Sita is left in asrama, and it is this illusory Sita that Ravana abducts. This is unknown in the Valmiki.
15. In Valmiki, it is Kabandha who advises Sri Rama to make friends with Sugreeva and gives details about the place of his residence, whereas in Adhyatma it is ascetic Shabari who first tells Rama about Sugreeva and informs him that Sita is confined in Ravana's palace.
16. After the death of Vali it is Hanuman who consoles Tara in Adhyatma Ramayana, whereas in Valmiki Sri. Rama gives her elaborate advice on the philosophy of Vedanta and the practice of devotion, besides consoling her.
17. In Adhyatma while Rama is staying at Mount Pravarshana after the coronation of Sugreeva, he gives an elaborate discourse to Lakshmana on the ritualistic worship of Lord Maha Vishnu (i.e. Himself), thus revealing his identity with the Supreme Being open.
18. Swayamprabha comes to meet Rama and praises Him, identifying him as Supreme Being. According to the advice of Rama, she goes to Badari to attain Mukthi. This episode is absent in Valmiki.
19. Sampati gives an elaborate discourse to the monkeys who meet him He quotes Sage Chandramas while telling about the divinity of Sri. Rama. This incident is available in Adhyatma only.
20. A conspicuous addition in the Adhyatma is Rama's installation of the Sivalinga in Rameswara, before the construction of Sethu for the success of the enterprise. Rama also declares about the merit of Pilgrimage to Rameswara and Sethu Bandha here. These elaborations are not available in Valmiki.
21. Sri Rama is well aware of his divinity during the Nagapasa arrow episode and Garuda’s arrival to release them. In Valmiki, Rama is not aware of his Divinity till the end when Brahma imparts that knowledge to him.
22. Kalanemi obstructs Hanuman while he is on his way to bring Mritasanjivani, a herb that can revive one who is almost dead. This incident is absent in Valmiki.
23. Narada praises Rama after the death of Kumbhakarna in Adhyatma. This is absent in Valmiki.
24. Killing of Maya Sita by Indrajit and illusion created thereon by black magic is available in Valmiki but not in Adhyatma.
25. Before going to battle Ravana, for gaining invincibility in fighting, begins fire rite, as per the advice of his guru Sukracharya. This rite is blocked and stopped by the monkeys. These incidents are absent in Valmiki Ramayana.
26. Rama cuts down the heads of Ravana repeatedly, but could not kill him. Vibhishana informs Rama that Ravana has got amrita deposited in his umbilicus and that until it is removed he cannot be killed. This is available in Adhyatma Ramayana. But in Valmiki Ramayana as per the advice of Sage Agasthya Rama chants Adhithya Hridaya and worships Lord Surya to kill Ravana.
27. According to Adhyatma on the death of Ravana, his spirit, having luminosity of lighting enters into Rama and attains moksha. This explanation finds no place in Valmiki.
28. After the death of Ravana, Sita's fire ordeal is only to replace the Maya Sita by Rama. The whole event is given the appearance of a real ordeal in Valmiki.
29. In Adhyatma Ramayana everyone praises and chants the hymn on Rama starting from Vamadeva, Valmiki, Bharadwaja, Narada, Viradha, Sarabanga River, Sutikshna, Agasthya, Viswamitra, Vasishta, Jatayu, Kabhanda, Sabari, Swayamprabha, Parasurama, Vibhishana, and Hanuman. This is absent in Valmiki's.

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