# What is the duration of a year on the Moon (Tropical/Sidereal period) for orbit about the Sun ? How/why does length of lunar days vary ? Soltices?

The inclination of the lunar equator to the ecliptic is 1.543°. Synodic period or Length of a day on the moon = 708.7344 hours

Moon Fact Sheet

100 Lunar Days - Parts I and II

• Hi, and welcome to SE. Can you try to formulate your question as you would ask a normal person? How do the random "facts" in your question relate to the several questions you ask in telegram style in the headline? Try to focus on one question. Please outline your own attempts in finding an answer and why and how they were unsuccessful. Please see astronomy.stackexchange.com/help/how-to-ask Aug 26 at 15:20
• A year is a year, no matter where you are. Asking "how long is a year on ..." is generally a layman's method of asking about the orbital period around its parent body, and you already know that from your link. If you want to ask something else, you will need to more clearly specify what you mean. Aug 26 at 16:52
• Thanks for the reply. Okay so I got the synodic period of the Moon (or a day on the moon) which is equal to 29.5306 mean solar days on earth . Now dividing mean solar year of earth 365.242 days (which I assume the time it takes for the earth-moon system to complete an orbit around the sun) by 29.5306 , I get 12.368. Therefore there are only about 12.368 lunar days in a lunar year. Is this correct ? For clarification I am trying to get the orbital parameters of the moon for its orbit about the Sun Aug 26 at 19:17