Marttanda are Adityas, or sun in Vedic philosophy. Marttanda are sons of Adity, who are referred variously as five, seven, eight or twelve in number. The eighth aditya was cast away by Adity. The rest seven Marttandas each represents a particular solar energy. The dwellings of Marttanda stand for planets. An old proverb says `The Seven allow the mortals to see their dwellings`.
The Brahamana and Puranas generally recognize twelve Marttandas, In a preceding Manvantara Marttandas were called Tushitas. At the end of that cycle they all entered the womb of Adity so that they could be born in the next Manvantara and could again enjoy the rank of gods. In the present seventh Manvantara Marttandas are known as Adityas. When the Pralaya (dissolution) would come, twelve suns will appear. The twelve Marttandas are twelve great gods of the Hindu pantheon, also they signify twelve months of the year and twelve signs of zodiac.
The Marttandas are sustainers of the solar divine life, which exists in all things. In our present Vaivasvata Manvantara the Marttandas or Adityas are divine solar pitris (fathers).