(Imām Bukhārī narrates): Musa bin Ismail narrated the hadith to us, he said: Juwairiyah bin Asma narrated the hadith to us, from Hazrat Ibn Umar (Allāh be pleased with them both), he narrated that

the Prophet ﷺ used to offer prayer upon his mount while travelling, whichever direction it faced, he ﷺ used to offer the night prayer by gesture, except the obligatory prayers, and he used to offer Witr upon his mount.