Ubayd bin Umayr relates that Sayyidah Aishah (may Allah be pleased with her) said: When the sun was eclipsed in the time of the Prophet (peace and blessings be upon him), he (peace and blessings be upon him) stood for a long time. He (peace and blessings be upon him) stood, then bowed, then stood, then bowed, then stood; then he (peace and blessings be upon him) prayed two rak'ahs with three bowings and four prostrations. Then he gave the salam, and the sun had become bright. When he (peace and blessings be upon him) bowed, he would say: 'Allahu akbar' (Allah is the Greatest), then bow; and when he raised his head from the bowing, he would say: 'Sami' Allahu liman hamidah' (Allah hears the one who praises Him). Then he (peace and blessings be upon him) stood and praised and extolled Allah, then said: "The sun and the moon are not eclipsed for anyone's death or life; rather, they are signs of Allah through which Allah, the Lord of Might, causes fear. When you see an eclipse, remember Allah until it clears."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب صلاة الخسوف / 6318