A Comprehensive Systematic Study of the first Two Chapters of S�rya-Siddh�nta with vivid examples based on the English Translation of the Bengali version of S�rya-Siddh�nta by �r�la Bhakti Siddh�nta Sarasvat� Thakur concisely presented by P�vaneshwar Das Sri S�rya-siddh�nta is considered throughout the history as the best book on astronomy based on mathematics. Most of the traditional Indian calendars (known as pancnga) are based on the mathematical calculations of S�rya-siddh�nta. Hence, the performance of our daily religious duties depends upon this book. Thus, this book must be read and understood. However, many consider that S�rya-siddh�nta is so difficult that it is impossible to understand. srila Bhaktisiddh�nta Sarasvat� Thakura says that, �Although it is difficult, it is not impossible to understand. If a person well versed in preliminary knowledge of mathematics reads the chapter from the beginning slowly, it is not difficult to understand. Of course, one has to do a considerable amount of computation, but it is not really that difficult.