Our ancient sages with their supreme knowledge and vast experience in astronomy and astrology expanded the potentialities in astro-meteorology also, and enacted relevant rules to predict the predominating natural phenomenons like weather, storm, rainfall, thunders and lightnings etc. It is a well known fact that the survival of all living beings is based upon the Pancha Bhootas or the five primordial elements viz Agni (Fire), Prithvi (Earth), Akasha (Ether), Jala (Water), and Vayu (Air) governed by Mars, Mercury, Jupiter, Venus and Saturn respectively. Out of the above, Jala or water is derived by rain which is very essential for the day to day life. Without rain the universe cannot get water by which all basic amenities like drinking water, cultivation, food production and electricity etc., are possible.
Our ancient sages made researches to predict the rainfall well in advance. In Vrihat Samhita, Varahamihira has illustrated various combinations for rains. There is also a detailed chart for predicting rain under the name ‘SAPTHA NADI CHAKRA’ allotting the stars of the zodiac as detailed below.
It can be noted that the stars are arranged in the first line from Krithika in ascending order and reverse in the 2nd line, ascending in the 3rd line and reverse in the 4th line. It may be seen that the star Abhijit is also included which is located in Capricorn Sign from 6º-40' to 10º-53' apart from the existing stars. Thus 28 stars are grouped into 7 groups with 4 stars each. From the name of the Nadis or groups itself their nature can be clearly understood. As such the first 3 nadis are of malefic nature being governed by natural malefics, while the remaining groups are benefic being governed by natural benefics
To predict the rainfall, the Moon’s position and other planetary conjunction in one and the similar nadi are to be considered. For example if Moon is posited in Watery or Jalanadi and if 3 or more planets are also in the same Nadi stars, it can be concluded that there will be good rain. So also if the above planetary position is seen in the Ambrosial or Amritha Nadi, it may bring rain for several days. The Malefic nadis will affect the rain badly. Like this there are many combinations which are to be carefully studied before making predictions for rainfall.
Our sages have formed all rules which are also connected closely with other matters. The Sanskrit word ‘Saptha’ gives the meaning of Number seven. The seventh house in the horoscope deals about the marriage. In Hindu marriage there is a custom termed ‘Sapthapathi’ i.e., walking seven steps with the husband which create new attachment in the wedded life. The great rishies or sages are seven in number who remain as stars in the heavens. As such in the said Saptha Nadi Chakra the star groups give further clues in the marriage compatibility also.
There are 12 points or Kutas for marriage compatibility between the bride and bride groom. These are 1. Dina (Nakshatra), 2.Gana, 3.Mahendra, 4.Sthree Dheerga, 5.Yoni 6.Rasi, 7. Rasi adhipathy 8.Vasya, 9.Rajju, 10.Vedha, 11. Varna and 12. Nadi. Out of the above 12 Kutas Varna, Vasya, Dina, Yoni, Rasi adhipathy, Gana, Rasi, and Nadi Kutas are alone considered as most important and thus they are assigned 1 to 8 marks each respectively, the total of which comes to 36 marks. Again it may be seen that out of these 8 Kutas, The Nadi Kuta (Vatha, Pitha and Sleshma) alone has been allotted with the highest marks of 8 in the matter of marriage compatibility. This is because, it tells about the physical condition, nervous energy or pulse of both the bride and bridegroom which are inherited on a hereditary basis. That is why it is insisted that both of them should and must be of different Nadi groups.
Now the stars of each Nadi or group in Saptha Nadi Chakra may be compared with those of the marriage compatibility points or Kutas i.e., Nadi, Rajju and Vedhas and the uniformity existing in them can be ascertained.
From the table given below of comparison it is understood that majority of the stars in the SapthaNadi chakra groups / are identical with the Nadi,and Rajju kutas in the marriage compatibility points. In respect of Vedha Kuta, the malefic nadis in Saptha nadi chakra are alone identical with marriage compatibility.