Aditya-Hridayam, a part of the Yuddha Kanda (the chapter of war) of Valmiki Ramayana, is a hymn in glorification of the Sun or Surya. This hymn was recited by the great Sage Agastya to Lord Rama on the battlefield before fighting with Ravana. This mystical hymn is directed to the Sun God, the illustrious lord of all victories.
Sage Agasthya Muni gave this powerful Mantra to Sri Rama when Rama was perplexed, while fighting with Ravana. After chanting this Hymn three times Sri Rama defeated Ravana.
Daily prayer to Lord Surya helps keeping good health and achieving victory in all aspects.