Abdullah bin Amr (may Allah be pleased with them both) says: The sun was eclipsed in the time of the Prophet (peace and blessings be upon him), and it was announced: "Gather for the prayer." He (peace and blessings be upon him) performed two bowings in one rak'ah. Then he stood and performed two bowings in one rak'ah, then he (peace and blessings be upon him) sat until the sun became bright. Aishah (may Allah be pleased with her) says: I have never performed a prostration or a bowing as long as that.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب صلاة الخسوف / 6311