Explore Chhath Puja 2026 dates, four-day rituals, Nahay Khay, Kharna, Sandhya and Usha Arghya timings, puja vidhi, Surya mantras and astrological significance for health, prosperity and happiness. Chhath Puja is a very holy Hindu festival of worship of Lord Surya (Sun God) and Chhathi Maiya. The festival is celebrated with immense devotion, particularly in Bihar, Jharkhand, Uttar Pradesh and West Bengal, marking a thanksgiving to the Sun, the supreme source of energy.