Here is full information about the system I use, which utilizes both the tropical and sidereal conceptions by taking tropical signs (rāśī) and sidereal stars (nakṣatra): vicdicara.com/tropical
The information there is very long. A very short synopsis is this: Indian tradition anchors the zodiac signs to the stars (“sidereal”), even though their source texts (the Purāṇas and Siddhāntas, etc.) anchor them to solstices and equinoxes (“tropical”). In deference to the source texts, which should be the source of tradition, I differ from the popular tradition and use tropical signs with sidereal nakṣatra.
Here are some specific questions I recently got:
Does this change the navamshas, which are the nakshatra pada?
Navāṁśa are divisions of the rāśī. Their borders move with the borders of the rāśī. Nakṣatra are independent of the rāśī. Therefore the correlation of navāṁśa to the nakṣatra – which is the basis for the concept of nakṣatra pada – is not permanent.
To be clear, 1º Aries is always the Aries navāṁśa. And 4º Aries is always the Taurus navāṁśa. But 1º Aries is not always Aśvinī nakṣatra (due to precession of the equinoxes), so the relationship between the navāṁśas and the nakṣatras are not permanent.
Thus the system I use destroys the concept of nakṣatra pada, which is one reason many people don’t like it.
If the Moon is at 23 degree Capricorn is this the later half of Uttarasadha or first quadrant of Shravana nakshatra?
“Capricorn” is a the 30º of solar space beginning from the sun’s southernmost point (southern equinox). The way this corresponds to the fixed stars/nakshatras changes slowly over the centuries. Currently 23º Capricorn is at the beginning of Uttarāṣāḍhā nakṣatra. About 2,000 years ago, 23º Capricorn was at the end of Śravaṇa Nakṣatra.
If the Moon was at 9 degrees sidereal Cancer, but is at 2 or 3 degrees tropical Leo then does that also shift pushya nakshatra into that region of space?
If I say that the soccer ball is three meters away from the street lamp, and someone else says it is 1 meter away from the mailbox – the soccer ball is in one place, but there are two ways to describe where that place is. One is in reference to the street lamp, the other is in reference to the mailbox. A soccer ball is like the Moon. The street lamp is like a star. The mailbox is like a solstice. The sidereal address of the Moon is such and such degrees away from a star. The tropical address is such and such degrees away from a solstice.
Please try to understand that “9º sidereal cancer is exactly the same point in space as 3º tropical Leo.” Since 9º sidereal cancer falls in Puṣya, then 3º tropical leo is falls in Puṣya (because it is the same point in space).
Now imagine that you move the street lamp. A wire connected to the lamp-post will move with that lamp. A wire connected to the mailbox will not. Nakshatras are fixed to stars. Rashi (signs) are fixed to solstices. If you move the solstice in relation to the stars (or visa versa), the relationship between the rashi and nakshatra will change. That is exactly what happens.
This is why 0º Aries was once in the same place as 0º Aśvinī, but that was just once upon a time. Now 0º Aries is at about 3º of Uttara Bhādrapadā
Please understand that the nakshatra are sidereal and are their own entities, they are not divisions dependent on the rāśī.