At the north and south poles of the moon, the sun is never more than 1.5 degrees above or below the horizon. The pattern of daylight and shadows produced differs from anywhere on the moon – or on Earth. After enlarging the area of small lunar heights near the South Pole, this visualization recreates the lighting conditions there over the course of two lunar days, equivalent to two months on Earth.
This is near the pole, the sun does not rise and set. Instead, as the moon rotates on its axis, the sun moves along the horizon, and it travels a full 360 degrees around the terrain. Mountains 75 miles (120 km) away cast a shadow across the landscape. With the sun at a low angle, it can never reach the floors of some deep potholes. The places the sun never reaches are known as permanently shaded areas. They are the sites of some of the coldest spots in the solar system, and because of that, they trap volatile chemicals, including water ice, which would instantly sublimate (convert directly from solid to gas) into the harsh, air-free rays of the sun that fall In most other places on the moon.
The Sun appears to move in a circle at the Earth’s poles as well, but it also moves across a range of heights. From the spring equinox to the summer solstice, for example, the Sun is climbing higher in the sky, reaching a height of 23.4 degrees. It only hugs the horizon for a few days around the equinoxes. The sun is at the poles of the moon Always Near the horizon, shadows are always long, sweeping over the surface as the solar azimuth changes.