What is birth time rectification? And when birth time rectification is required?
Birth time rectification is a process to find the correct birth time of the native so that we can draw the birth chart for predicting the life ahead.
Every planet casts its influence on the native as per its positioning at that time. Every combined positioning of the planet is so unique that it may take hundreds of years for two horoscopes to be the same. Therefore one must understand what is the significance of correct birth time.

Correct birth time is essential for predictions in astrology.
The three main components to form a horoscope are birth date, time of birth, and birthplace. Even a slighest of variation in any of these will change the planets' positioning in the horoscope. The predictions are based on the positioning of the planets in the horoscope. Therefore the slightest change in the positioning of the planets will result in an altered prediction. A little change in birth time, say even to the tune of one second, can alter the planets' positioning and thus the prediction. Hence we should know that birth time is essential in astrology.
Take the case of twins born one minute apart. Despite being born just a minute apart, both have distinctly different behaviors, likings, and temperaments. They grow up to have different lives and fate. Therefore, it is immensely necessary to have the correct time of birth before getting a prediction done.
Birth time verification is a technique that should be applied by an astrologer before actually reading the horoscope. In this technique, the astrologer tries to verify a few events of the recent past. If these events get confirmed, then the astrologer becomes sure of the birth times.

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