Sade-Sati is the 7½ years long period of Saturn (Shani). The period starts when Saturn penetrates into the zodiac sign immediately before the zodiac sign of natal Moon (where one\'s Moon is placed in the birth chart) . i.e., if the Moon sign (Ayamsha) at the time of birth of the personage was Taurus, then the Sade-Sati will begin when Saturn enters the sign Aries. The Sade-Sati will maintain while Saturn travels over this sign and the next two signs in the order. Saturn spends around 2 ½ years in each sign. Therefore, to cross these three signs it takes about 7 ½ years.
This astrological phase is apprehensive for those who give credibility to Indian Astrology. The period is believed to be challenging, full of disappointments, disputes, differences etc. Its impact is supposed to be felt differently by people of different moon signs. For example- the beliefs are that the people of Moon sign Aquarius do not have any ill effects from Sade-Sati, while people of Moon sign Leo feel the most impact. While other Astrology school condemn these beliefs and vouch that it is not as damaging as many astrologers claim, and that many people achieve a lot of success during the period of Sade-Sati.
Sade-Sati is divided into three phases called Rising, Peak and Setting and the results of Sade-Sati vary as per the phase the person is going through.
Another related astrological transit of Saturn is the Dhaiyya (2 ½ years), also known as Small Panoti (Small Trouble), Kantakshani, or Ashtamshani. This journey of Saturn is marked when it is transiting through the 4th sign from the birth Moon sign (Kantak Shani), or from the 8th sign from the birth moon sign (Ashtamshani). According to Vedic astrology these two are hazardous periods, though not as much as the Sade-sati. But if there is a proper system then this period of Sade-Sati will not affect any human being.