Ona suryodayam

The innermost circle depicts the Lord Surya and the shades around it is the 7 horses of his chariot, which also depicts the 7 days of the week, the 7 colours of the light. The next five circles depicts the the day and night which causes seasons nd harvests. Onam is our harvest festival. The next is the sudarshana chakra. Vishwakarma created the sudharshana chakra by reducing the brilliance of lord Surya, so his daughter Sanjana, married to Surya can approach him. The Sudharshana chakra is lord Vishnu's ayudha and he in the Vamana avatar sent King Mahabali to Pathala, on the third step. The outer three circles depict the effects of Sudharshana chakra - peace and prosperity, ward off all evils and good health.