This is the waxing crescent moon as it appeared on September 9, 2021.

Many of the features you see on the moon are impact craters – there are about 9,000 of them. The darker regions are called Mare, meaning ‘sea’ in Latin – these are regions formed as a result of volcanic activity a long time ago, and there are 22 of them. There are smaller darker regions called Lacus, which means ‘lake’ in Latin, and there are 20 of them.

Visible in this image is Mare Crisium at about the 2 o’clock position; just above Mera Crisium, the crater Cleomedes; just above the 3 o’clock position is the crater Langrenus and Vendelinus below it; the barely visible crater Vega at about the 5 o’clock position located between the light and shadow.

The moon is tidally locked, which means the same side of the moon is visible to us all of the time. The other side of the moon is often referred to as the dark side of the moon, yet this name is wrong because it also has phases like the side of the moon that faces us. Satellites have taken images of the other side of the moon and have mapped the region.