It is narrated from Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) that the Prophet (peace and blessings be upon him) said: "The sun and the moon do not lose their light because of anyone's death or life; rather, both of them are among the signs of Allah. When you see them in this state, then pray."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب صلاة الخسوف / 6355