राशि(zodiac sign) of Krishna and Rama
Zodaic specially refers to position of moon in constellation at the birth time. Although Sun-zodiac is also calculated, but the term राशि mainly refers with respect to Moon.
For Lord Krishna
1-5. Thereafter, at the auspicious time for the appearance of the Lord, the entire universe was surcharged with all the qualities of goodness, beauty and peace. The constellation Rohini appeared, as did stars like Asvini. The sun, the moon and the other stars and planets were very peaceful. [10.3 Srimad Bhagvat]
Also in Padma Puran
Padma Purana 4.13.27
Having rested in (Devaki's) womb for nine months and nine days, the lord of the world, the enemy of Karhsa and the son of Vasudeva, was born (on) the night when Rohini was in conjunction (with the Moon), when clouds were thundering, of the day called Astami, (falling) in the dark fortnight of the month of Bhadrapada. Yasoda, the daughter of Virata and the wife of Nanda, gave birth to a daughter. Anakadundubhi (i.e. Vasudeva)
Hence from above informations Lord Krishna was born in Rohini nakshtra Rohini nakshtra falls in 'वृष' / 'vrish' / Taurus constellation.
Hence राशि of Lord Krishna is वृष/vrish/Taurus ।
For Lord Rama
Valmiki Ramayan Bal Kanda
ततो यज्ञे समाप्ते तु ऋतूनाम् षट् समत्ययुः | ततः च द्वादशे मासे चैत्रे नावमिके तिथौ || १८-८ नक्क्षत्रे अदिति दैवत्ये स्व उच्छ संस्थेषु पंचसु | ग्रहेषु कर्कटे लग्ने वाक्पता इंदुना सह || १८-९ प्रोद्यमाने जगन्नाथम् सर्व लोक नमस्कृतम् | कौसल्या अजनयत् रामम् सर्व लक्षण संयुतम् || १८-१० विष्णोः अर्धम् महाभागम् पुत्रम् ऐक्ष्वाकु नंदनम् | लोहिताक्षम् महाबाहुम् रक्त ओष्टम् दुंदुभि स्वनम् ||१८-११
Twice six months had rolled a way since the great sacrifice was over and, in the first month of the New Year, on the ninth day of the bright fortnight, the Lord of the worlds chose to take human form and sent down half of His essence as the son of Kausalya (thenceforth to be known as Rama), the world-honored One, the crowning glory ot the grand line of Ikshwku, and the sum of all perfections. The constellation Punarvasu, of which Aditi was the regent, was chosen to preside at his birth. The Sun, Mars, Jupiter, Venus, and Saturn were in ascension in their respective houses. Aries, Capricornus, Cancer, Pisces and the Libra, Jupiter and the Moon were in conjunction ; the rising sign was Cancer. And KausalyA, shone with unparalleled effulgence, even as Aditi when she gave birth to Indra, the lord of the Shining Ones, the Vajra-wielder.
From above Lord Rama was born in Punarvasu constellation. Punarvasu constellation falls in two zodiac, the first third quarter falls in 'Mithun' and last one quarter falls in 'karkat'.
But the verse also says Jupiter was in Karkat ie. Cancer. Also it says Moon and Jupiter were in conjunction. It means moon was also in Karkat.
Hence राशि of Lord Rama is कर्कट/karkat/Cancer ।
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