Lunar Day One
As we start our explorations of the lunar surface together, let us start by talking about how this section is divided. Factually, a lunar day is the period of time it takes for the Moon to complete one full rotation on its axis with respect to the Sun. Equivalently, it is the time it takes for the Moon to make one complete orbit around the Earth and come back to the same phase. It is marked from a New Moon to the next New Moon. To find these times and calculate the lunar day, just reference the tables you will find in the back of this book - but first you will need to learn just a little bit more!