Jyautiṣa or astronomy is Vedāṅga, a subsidiary science that helps in determining suitable times for the performance of Vedic sacrifices.
Over the centuries, Jyautiṣa evolved into a much larger and much more complicated science, embodying in itself, not onlyastronomy, but also astrology, the science that predicts the influence of the planets and other heavenly bodies on human affairs.
One of the basic works on Hindu Astrology is the Bṛhatsaṁhitā of Varāha-mihira (6th century A.D.). Though it deals mainly with astrology, it is quite encyclopaedic in its scope and includes several other branches of knowledge as geography, architecture, iconography, gem-therapy and so on. Each of these subjects has been treated, keeping in view its significance as an augury or its astrological effects. For instance, the section on rubies describes how one can know the quality of a gem, but it also gives the effects of wearing a good ruby.
Another interesting feature of this work is its 104th chapter. The various stanzas that deal with the astrological effects of the planets are composed in different meters, the name of the meter itself being ingeniously included in the verse itself.