Vedic astrology is the oldest of the existing astrological teachings. Only in the written form it is about 5,000 years old. All other teachings come from vedic knowledge of astrology.
Vedic astrology operates with planets called Grahas. Graha means - the one who holds. In our case, grahas are holding human karma. Sounds incredible? Below will be even more incredible.
Human karma is written in form of Sanskarah. Sanscaras are fine vibes. Sanskaras are recorded in human consciousness. The corresponding planets vibrations correspond to certain human vibrations of sanskaras of person in his consciousness.
How to determine what my consciousness is and what is recorded there? Very simple - look around you. Everything you see is recorded in your consciousness, because your life is the reflection of your consciousness. You will not see in your life and will not come up with anything that is not recorded in your consciousness.
Horoscope and planetary arrangement
Earth is circling around the Sun, so astrology predominantly uses the known planets of the solar system. It is because we are directly affected by the Sun. If the Sun goes out, we will not be in the next second. Imagine these planets most recently discovered were very well known to the ancient civilizations that have passed this knowledge to us.
The planets in horoscope are positioned according to its actual location in the sky at a specific time and location. We use the topocentric approach. This is because it is important how the planets are placed against the particular person, but less important is how they are located against the center of earth.
The planets are located in a horoscope of 12 parts. We call the part Bhava or Rashi, others call her house or zodiac. Meantime, the planets are located in 27 constellations called nakshatras.
The person itself is determined by the ascendant or lagna.
An astrologer, when analyzing a certain horoscope, looks at where the planets were at the time of human birth. Different conclusions can be drawn from this information. Each planet is a significator of something. The same with bhavas and rashis.
For example, if the papagraha (malefic planet) Mangala (Mars) is located in 12th bhava from 5th bhava and feels bad, it can mean that a person may have abortion. If shubha graha (benefic planet) Shukra or Venus is located in your 2nd house and it is swakshetra (feels good, and is at home), you may be rich person.
Why does it work?
We can ask the other way - why does nothing else work? You may ask - why it does not work? An example - everyone wants to be slim, healthy, rich and live forever. The question is - does everyone succeed? Of course no. This is because not all people in karma are supposed to be thin, successful, healthy, rich. In fact - life is like a cinema screen, where the person itself is just a viewer with very good graphics.
I have seen in my life a lot of situations in which a person's life is very good: he is rich, successful, but suddenly the astrological situation changes - and everything changes by 180 degrees.
Why is it? Because mahadasha has changed - a great period of life. This period is ruled by another planet, the task of which is to teach something else to this person.
Is it possible to somehow influence my life?
Yes it is possible. But, it will never be possible before you become aware of life's teachings. One of the main tasks of life is to understand that it is not you who determines your life, but it is determined up there. Then you have to start the path of spiritual development. You need to learn to speak the planets in the language of karma. You must learn to understand the situation behind which stands the planet. You need to understand what lesson planet wants you to learn.
The higher level of karma change is Vedic and Tantric Upayas.