One of the main principles of the traditional transit theory is Sade-Sati of Saturn.

SADE SATI OF SATURN: TRADITIONAL THEORY

Saturn transits a sign for approximately two and a half years. Whenever Saturn enters the 12th house from the Moon of a particular native, he is said to have started having the period of Sade-Sati that is 7 and 1/2 years which Saturn will take in transiting 12th house, the Moon sign and the second house from the Moon sign. Malefically disposed Saturn to a chart until and unless under check by powerful trinal aspect from benefic Jupiter inflicts maximum pains/misfortunes to the native. Persons having their Moon signs lorded over by Saturn and Venus are, however, believed to be free from the results of Sade-Sati, provided the radical Saturn is strong.

SADE SATI OF SATURN: SYSTEMS APPROACH

The traditional theory of Sade-Sati of Saturn does not hold good. Saturn, when a functional benefic, does not cause harm while in any of the houses, during its transit. However, when in the 6th, 8th or 12th houses to the natal ascendant, it fails to bestow the significations ruled by it. When a functional malefic, it causes harm in all houses when coming into close conjunction/aspects with natal positions of the planets.

However, the traditional theory does not hold up in a scientific study. This is, perhaps, the easiest way of convincing oneself that he/she has found out the reasons for the sufferings of people coming for astrological advice. In fact we have to see the functional nature of Saturn with reference to the ascendant. If Saturn is a functional benefic, it will bestow good results while in the ascendant and the second house. While transiting the twelfth house, such a benefic Saturn, and at the same time its sub-period being in operation, will not produce bad results but its capacity to do good will be restricted due to weakness attained by transiting the twelfth house. Assessment of sub-periods of planets after due consideration to the strength of the planets in transit in relation to natal positions prove more meaningful.

As per the 'Systems Approach', Saturn is a functional benefic planet for Aries, Taurus, Gemini, Leo, Libra, Scorpio, Sagittarius, Capricorn & Aquarius ascendants. Therefore, sade sati is not applicable for those who are born in these signs.

Saturn is a functional malefic for Virgo, Cancer and Pisces ascendants. For persons born in these three ascending signs the impact of Saturn during the course of Sade Sati is explained hereinafter. Therefore, the mal-effects of transiting Saturn are felt by the natives who have any of these signs as an ascendant.  As already indicated, the results are only to be analyzed with reference to the ascendant.  Moreover, unfavorable results are not felt throughout the period for seven and a half years when transit Saturn is in the twelfth, first or second houses. The mal-effects would be felt only when Saturn forms conjunction with the most effective points of the twelfth, first and second houses and when it forms exact/close conjunction/aspects, with weak natal planets.  Barring the period of transit conjunctions/aspects, the rest of the period of seven and a half years would be as per the trends set by the main period lord, sub-period lords, the strength of sub-period lords and transit influence of other planets.

Under SA a functional malefic Saturn:

(i) while transiting the MEP of the twelfth house, Saturn causes problems relating to disturbed peace, inflated expenses, loss of status and reputation, conflicts and controversies and causes a fortune setback.

(ii) while transiting the MEP of the first house, it causes problems relating to natural calamities, public unrest, associates turning hostile and setbacks in professional/business ventures.

(iii) while transiting the MEP of the second house, it causes problems relating to loss of wealth, status and harmonious relationships, causes serious setbacks and curtails the incomes besides causing mental unrest.

Besides the above the triple transit impact of Saturn during the course of the 7 and a half years causes setbacks/harm to the significations of the natal planets influenced.

SADE SATI OF SATURN - ASTRAL REMEDIES:

Propitiation: Giving food to beggars and poor people. Give part of breakfast to the birds.
Strengthening of Planets: Strengthening of weak functional benefic planets through a special power kavach cum gemstone pendant.