There are various systems or schemes of astrological Nakshatra. One is based on the 27 Nakshatra system, and the other is 28 Nakshatra. Before we dive deep, it’s important to understand the broad picture first.

One lunar cycle is 27 days plus 7 hours approximately. We can round it off from the lower portion of 27 Constellations to the upper portion of 28 Constellations. If we divide all the 12 zodiacs across 360 degrees measurement of the sky, further divided into 27 parts, we will get 13 degrees 20 minutes for each Nakshatra.

This is done assuming that the motion of the Moon is uniform across all the Nakshatras (lunar mansions) which takes one day for a complete revolution. In reality, it takes less time, but for the convenience of calculation, it is rounded off to 24 hours.

In Vedic Astrology, they have realised that the motion of the Moon is not uniform – it accelerates and decelerates in different Nakshatras or constellations. That is why Vedic Astrology is a far more intricate system. It is called Creation Nakshatra or Shrishti Nakshatra.

Here’s an example – according to the general astrological system, Ashwini Nakshatra ranges from 0 to 13 degrees 20 minutes in Aries, and so on for the following Nakshatras. But ‘Bramha’, in the Creation Nakshatra system, has assigned different lengths for each Nakshatra based on the actual speed of the Moon.

This doesn’t end here. Each Nakshatra has four ‘Padas’. The first pada is Agni (fire) tattva, the second is Prithvi (earth) tattva, the third is Vayu (air) tattva, and the fourth is Jal (water) tattva. From these four Padas, Nakshatra aims are derived, which are Dharma, Artha, Kaam, and Moksha. These four Padas are like four legs of the Bull, wherein Moon represents the Bull that visits each Nakshatra (cows).

During Satyuga, all four legs of the Bull were strong, which means all the elements were strong. In Dwaparyuga, three Tattwas were strong; in Tretayuga, two were strong, and currently, in Kalyuga, only one element is strong. This is why in Kalyuga, it is important to look at Pada Nakshatra to understand which pada is most intense. In other words, in Satyuga, the Moon had that kind of strength that when it travelled through a Nakshatra, it lit up all the four Padas of that Nakshatra.

Every Nakshatra pertaining to a pada is a map of a certain kind of destiny. So if your Moon is in Agni Rashi or Zodiac, that means Agni Rashis are strong in the chart. Moon represents the mind, and ultimately it is the mind that matters most; certain pada being strong, planets in that pada will perform best.

There are different reasons for starting the count for Nakshatras. The first one starts with Ashwini Nakshatra, the second one starts with Krittika Nakshatra, and the third one starts with Ardra Nakshatra. It is based on the Sun, Moon and Rahu since Sun is the boss of the whole zodiac and exalted in Aries, which is the sign of Ashwini Nakshatra.

Hence, this becomes the first in the Nakshatra count. Now, in the second perspective, the Moon is exalted in the second degree of Taurus, which is Krittika Nakshatra. Thus, this becomes the first to be counted under Moon placements. The third is Rahu which does not surrender to the Sun or Moon, and it is the lord of Ardra. So, Ardra becomes the first in the count. These are three schemes of Nakshatra – Ashwinadi, Krittikadi, and Ardradi.

All the Dashas allocation, such as Vimshottari Dasha, starts from Krittika since it is based on the Moon; and Moon is exalted in Krittika. Vimshottari Dasha is a 120 years long planetary cycle giving an overview of situations in a native’s life along with the influences of major and minor planets.

In the 27 Nakshatra system, there is a concept of ‘Navtara’ that means a set of nine stars. Hypothetically, it is categorised as nine stars on each side of a triangle representing creation, sustenance and destruction or Bhurloka, Bhuvaloka and Swahaloka – Bhurbhuva Swaha mantra is about this. These three Lokas or planes are three manifested worlds, not spiritual worlds.

For spiritual worlds, another system of Nakshatra comes into the picture, and that is the 28 Nakshatra scheme. This is represented by a hypothetical square containing seven sets of stairs on each side. Each side being Maharloka, Janaloka, Tapoloka and Swargaloka. This square is called Jagannath or Chok. If someone understands Orissa dance, it is a very spiritual dance because it is based on Chok.

Every zodiac covers 2.25 Nakshatras. That means two Nakshatras and one-fourth of the following third Nakshatra. Hence, there are 9 Padas in every zodiac as one Nakshatra has four Padas. Nakshatras have Nakshatra lords or deities, who play an important role in specifying the planetary motivation for natives. They change the influences of planets to a certain level.