When the planet moon is malefic, worship of moon yantra will be very beneficial. Chandra yantra is kept in the house to negate the malefic effects of the planet. Chandra yantra can help maintain the mental balance of mind and bestow peace of mind. Position of moon in horoscope can affect the behavior of a person. Worship of moon yantra can help you to maintain your mental and emotional life which is because of the result of weak placement of moon in the birth chart.