Lunar day around the Sun at the same time, the Moon must travel further to return to the same phase. On average, this synodic period lasts 29 days, 12 hours, 44 minutes, and 3 seconds. This is the mean figure since the speed of the Earth–Moon system around the Sun varies slightly during a year due to the eccentricity of its elliptical orbit, variances in orbital velocity, and a number of other periodic and evolving variations about its observed, relative, mean values, which are influenced by the gravitational perturbations of the Sun and other bodies in the Solar System. As a result,
Mithuna (month) solar month of Karkaṭa. The Mithuna month is called "Ani" in the Tamil Hindu calendar. The ancient and medieval era Sanskrit texts of India vary in their calculations about the duration of Mithuna, just like they do with other months. For example, the "Surya Siddhanta" calculates the duration of Mithuna to be 31 days, 15 hours, 28 minutes and 24 seconds. In contrast, the "Arya Siddhanta" calculates the duration of the Mithuna month to be 31 days, 14 hours, 34 minutes and 24 seconds. Mithuna is also an astrological sign in Indian horoscope systems, corresponding to Gemini (astrology). Mithuna (month)