Saturn is the slowest moving planet in our solar system. In Sanskrit language its known as Shanay-char also. Shanay in Sanskrit means slow and Char means to move. As per Vedic astrology Saturn rules the direction West, its color is Black and dominates our old age. Saturn is significant for metal Iron, barren land, things buried deep into earth, oil and gas, natural calamities, accidents, surgeries, attack by a robber or thief, robbery and theft, stealing by servants or people working for you, all kind of hard wares, advance technology, space, airplanes, ships, cars and other mode of travel. Saturn is also significant for lawyers, judges, courts, fine by courts or government and controls isolation, separation and depression part of our life. As per Vedic astrology when Saturn enters the house earlier than the Moon sign, the Sadhe Sati or the 7 1/2 year cycle of Saturn starts. Why 7 1/2 years, because Saturn stays in one house or in the house earlier than Moon for about 2 1/2 years and then on top of Moon sign for another 2 1/2 years and then moves away from Moon sign or the house next to it and stays there for 2 1/2 years, so this transit of Saturn on and around Moon is better known as Saturn's Sadhe Sati. Since Saturn governs the law, it serves justice during this time and one has to pay for the blunders or mistakes committed earlier.
In first part Saturn enters the house earlier than Moon or the 12th house. In Vedic astrology, the 12th house is significant for expenses or losses, so if Saturn is adversely placed in the chart, it can cause losses or expenses through all areas mentioned earlier, for an example one may buy expensive cars beyond one's means, buy bigger property, get involved in litigation and may have to spend lots of money on lawyers hoping to win or may be falsely implicated in crime he never actually committed. May have to travel more than usual and get no results out of them or stretch his limits, borrow lots of money and buys a gas station.
Now after 2 1/2 years the Saturn enters the house occupied by Moon. Saturn being a bitter enemy of Moon as per Vedic astrology, creates lots of confusions n one's life. The person can not think straight and end up making wrong decisions or choices. He is always running around, has to work extra hard for very small gains, some times gets isolated from near and dear ones and may go into depressions also. In some cases this Saturn starts the process of Divorce also in one's family life. Since Saturn at this point is transiting on top of Moon or the First house from Chandra Kundli the person may get involved in accidents, break bones or may have to undergo surgery to correct the health issues. Now at this time the investments made in the past will start to give problems and other issues like litigation etc will increase the stress level and such conditions will continue till Saturn stays over the Moon in natives birth chart.
Then Saturn enters the house second from Moon for rest of the 2 1/2 years of sadhe Sati. Second house in vedic astrology denotes family and finances and this transit of Saturn can separate one from both. The person may be separated from family in some way, either temporary or permanent depending on many factors in one's birth chart. He may start to suffer financial losses on investments made earlier and may have to shut down business because of lack of finances or suffer financial losses through litigation or may have to pay fine or penalties to government also. The person will use all his savings in order to stay operating the business and ultimately run out of money to the extent that he may even file for bankruptcy. One may loose a big position or job and may have to work for a inferior position to support himself.
Now how Sadhe Sati or Saturn will react during this time depends on may factors and mainly they are the ascendant, sign where Moon is placed in one's chart and the placement of Saturn in the birth chart. For an example people having Moon in Virgo will suffer only during first 2 1/2 year of sadhe sati as Saturn will be transiting inimical sign Leo for first 2 1/2 years and the will transit friendly sign of Virgo and Libra there after and in case where the Moon occupies Libra in the birth chart, first 5 years of sadhe sati will not be bad as again Saturn will transit friendly signs Virgo and Libra but the last part of Sadhe sati will be bad as Saturn will transit its bitter enemy house and that is Scorpio. So only a careful analysis of chart can determine as to when and what will happen during sadhe sati of planet Saturn. Bottom line, Sadhe sati can make it or break it depending on one's chart.