Sahih Bukhari, Chapter: Eclipses

When the sun eclipsed in the lifetime of Allah's Apostle and an announcement was made that the prayer was to be held in congregation. The Prophet performed two bowing in one Raka. Then he stood up and performed two bowing in one Raka. Then he sat down and finished the prayer; and by then the (eclipse) had cleared 'Aisha said, "I had never performed such a long prostration."