Relationship of 120 years and Kaliyuga

This complete longevity of 120 years is represented by 120 degrees of the zodiac based on the Time-space equation from Manu Smriti whereby one day of the Deva is equal to a year in the life of human beings. By the term Deva (derived from Diva) the Soorya is referred to and its average daily motion of one degree in the zodiac. Thus 120 human /earth years would correspond to 120 degrees in the zodiac.