Aryabhatt Vedic Lession
Aum ! May He protect us both (the teacher and the disciple) together. May he sustain us both together. May we attain vigour together. May the learning of us both be resplendent. May we harbour no mutual ill will.
Aum ! Peace ! Peace ! Peace ! Peace !                                                  Kathopanishad
Astrology is as old as Vedas themselves. The Vedas which are the sacred Hindu scriptures, embody eternal knowledge. Strict moral and spiritual practices along with the deep study are prerequisities to understand the essence of Vedas. To the uninitiated, the Vedas might appear as nothing more than ritualistic oblations to air, water and thunder etc. Deep truths, however begin to unfold to the true seeker as his search goes on.
In time of yore, sincere seekers of truth and knowledge in India used to spend years and years at the feet of their 'gurus', learning the meaning hidden in Vedas. In order to decipher what lies concealed in Vedas, a study of certain subjects is considered a prerequisite. These subjects are called the 'Vedangas' or the body organs of the Vedas. There are six such vedangas. They are :

(A) Shiksha : Which deals with the understanding of  the Vedic 'Varanas', 'Swaras' and Mantras, and thus with the technique of correct pronunciation.

(B) Chhanda : Dealing with the appropriate lyrical utterance of  the Vedic 'Suktas'.

(C) Vyakarana : Expouding the grammatical aspects of the language.

(D) Nirukta : Which explains the difficult words, 'padas' and 'mantras'.

(E) Kalpa : Dealing with the understanding of Sutras and the use of Mantras, hence concerned with the ritualistic aspects of the Vedas.

(F) Jyotisha or Astrology : Of the body called the Vedas, astrology represents the 'eyes' with its capacity to see the past, the present and the future. Astrology is considered as the most important of the Vedangas.

What is Astrology ?
Astrology is the scientific study and application of language of the heavenly bodies. These heavenly bodies determined on the basis of Astronomy and mathematics, are mapped in the form of a horoscope. Their specific locations in the horoscope indicate specific happenings in the case of individuals, of multitudes and of geographical regions. Whether the Sun, the Moon, the planets and stars themselves influence the terrestrial phenomena, or they only indicate such phenomena by their various dispositions, is immaterial. What is important to us is that variations in their disposition determine variations in the events on the earth; the correlations are only too strong to be brushed aside by critics of Astrology.
Who should practise astrology ?
In the ancient times, a strict code of conduct was demanded of those who practised Astrology. A guru would teach astrology only to deserving disciple who would adhere to such a code of conduct. The guru-shishya (i.e., the teacher-disciple) tradition is already long over in India. With changing times, it has become difficult to find an appropriate 'guru' and a deserving 'shishya' to pursue this scared study within the rules laid by the sages of yore. It is, however, quite in order to be aware of this ancient code of conduct. Varamihira, the celebrated authority on astrology, prescribes the following qualifications for an astrologer :
(a) Physical features : According to the said author , the physical feature reflect the inner nature of man. The astrologer must be good to loom at, with all his body parts complete and healthy. He should be of sound health, with sound hands, feet, nails, chin teeth ears, forehead and head, and having a loud and impressive voice.
(b) Moral soundness : He should be truthful, gentle, bereft of cravings and aversions, clear of heart, not inclined to be critical of the qualities of others, devoid of base and wordly distractions.
(c) Behaviour in an assembly : He should be clever, able to express himself, bold in an assembly, not intimidated by his fellow astrologers, dignified and aware of the constraints of social and historical circumstances.
(d) Proficiency in the subject of Astrology : He should be well-read, and proficient in the three branches of Astrology known as Ganita, the Samhita and the hora. He must have studied the five siddhantas (or mathematical treatises). His mathematical proficiency must include the knowledge of various divisions of time, from the gross one like yuga to the finer ones. He must also possess knowledge of the various divisions, including the finest ones, of the zodiac.
(e) Proficiency in various branches of Astrology : The astrologer is required to possess a knowledge of different aspects of astrology which deal with propitiation of planets, rendering the planets beneficial or hostile, conducting religious ceremonies, and rituals which help neutralise the natural calamities.
(f) Defence of Astrology : The astrologer must be able to answer queries, and also pose relevant questions where appropriate. When necessary, he should be able to dazzle others by his knowledge, only to increase the dignity of astrology.
The Sage Parashara advocates a similar code of conduct for astrologers, stressing particularly on the necessity for technical intellectual and moral excellence; the capacity to weigh the pros and cons of a situation, along with the ability to synthesize a coherent prediction based on sound knowledge of the principles, sometimes apparently contradictory, of knowledge.
Sub-Divisions of Astrology
There are three main sub-divisions of Astrology.
(1) Samhita : This deals with collectivity or multitudes. It encompasses such varied areas as weather forecasts, agricultural produce, natural disasters, floods, famines, wars, earthquakes, cyclones, market trends, changes in government, national and international events, and virtually anything that influences the masses. The annual world predictions which are generally based either on Hindu New Year commencing on the Chaitra Shukla Pratipada, or on the solar Ingress into Mesha, fall under the Samhita astrology.
(2) Siddhanta or Tantra or Ganita : This deals with the mathematical aspects of astrology. There are several treatises on Siddhanta Astrology but five among them are considered as particularly important. They are :

(a) Surya Siddhanta

(b) Paulisha Siddhanta

(c) Romaka Siddhanta

(d) Vasishtha Siddhanta

(e) Paitamaha Siddhanta

A proficiency in these is considered as a prerequisite for a good astrologer, according to to the celebrated Varahmihira.
(3) Hora : It deals with :

(a) Individual horoscopes, or Jataka, or natal charts of a person.

(b) Muhurta or electional Astrology, which concerns itself with the election of favourable planetary dispositions to achieve specific accomplishments in day-to-day life.