When astrology starts with the self, it begins with an individual’s natal chart. The natal chart is a snapshot of the sky as it appears from the earth at the moment of your birth. It contains the location of all the planets and other celestial bodies in the solar system and the degrees of the twelve signs and another component called the astrological houses. Once, when we had to calculate it all by hand, this was like doing one rather complex math problem. Fortunately, computers can do all the work today, making it a simple process to get a copy of your own.
The chart is constructed based on the time and the location of birth. Knowing your time of birth to the minute is essential for the highest degree of accuracy. The degrees of the signs and houses and positions of planets are based on the exact longitude and latitude of your birth along with the time. Only minutes could potentially make a big difference in a natal chart. So, your natal chart is like a fingerprint. Someone would have to be born at the same exact time in the same hospital or building in order to have the same exact natal chart. Even twins, born only minutes apart, can have important differences in their natal charts. If you don’t know your time of birth, a good astrologer can often figure it out based on some of your life events.