Amshuman is a figure in Hindu mythology, one of the twelve Adityas. The Adityas's were all the sons of Aditi and Rishi Kashyapa. These twelve Adityas are actually different forms of Lord Surya. Each Aditya rules a month in the year.
Amshuman is said to be present in the Wind. Surya takes the form of Amshuman in the month of Aashada(July). The number of rays(power of the Sun in that Month) of Amshuman is said to be 15.
Amshuman arrives in a chariot in the Shita(Winter) season.