Whenever something pleasing came to the Prophet ﷺ or he received good news, he would fall down in prostration as an expression of gratitude to Allah .
حدثنا عبدة بن عبد الله الخزاعي وأحمد بن يوسف السلمي قالا حدثنا أبو عاصم عن بكار بن عبد العزيز بن عبد الله بن أبي بكرة عن أبيه
أن النبي ﷺ كان إذا أتاه أمر يسره أو بشر به خر ساجدا شكرا لله تبارك وتعالى
Its chain of transmission is hasan. Abu Dawud narrated it in the Book of Jihad, chapter on prostration of gratitude, hadith 2774, from the hadith of Abu Asim, with this chain. Tirmidhi said, hasan gharib, hadith 1578. Busiri said, it is a mawquf narration, but its chain of transmission is sahih and its narrators are trustworthy.