Near side of the Moon

Common card · No. 336937

The near side of the Moon is the hemisphere of the Moon that is facing Earth. While Earth keeps turning through its near side to the Moon, changing in the course of a day the part it faces toward the Moon, the Moon keeps the same surface (or "face") oriented to Earth. This is due to the Moon rotating on its axis at the same rate that the Moon orbits Earth—a phenomenon known as tidal locking. The opposite hemisphere is the far side. The Moon is directly illuminated by the Sun, and the cyclically varying viewing conditions from Earth cause the lunar phases. The near side when dark is faintly visible due to earthshine, which is indirect sunlight reflected from the surface of Earth and onto the Moon. Since the Moon's orbit is both slightly eccentric and inclined to its equatorial plane, libration allows up to 59% of the lunar surface to be visible from Earth over the course of a sidereal month (though only half at any moment from any point).

Read on Wikipedia · Image Peter Freiman Cmglee Background photograph by Gregory H. Revera, CC BY-SA 3.0