Time

Terraria features a day/night cycle that affects the light and the enemy spawns. Torches become the only light source at night, and monsters such as Zombies and Demon eyes spawn. There are clocks that can tell time. You cannot tell if it is day or night when you are underground without use of a watch or dropping a fallen star.

Day lasts from 4:30 AM until 7:30 PM, and night lasts from 7:30 PM until 4:30 AM. This means that Day lasts 15 hours, and night lasts 9 hours. Additionally, a game hour is a real life minute. Therefore, there are 15 minutes of day, and 9 minutes of night.