Why is the temperature of the dark side -200f?

The temperature of the "dark side" of the Moon, often referred to as the side facing away from the Sun, can drop to around -200°F (-128°C) due to the lack of an atmosphere to retain heat. Unlike Earth, the Moon has a very thin atmosphere, meaning it cannot trap heat during the lunar night, which lasts about 14 Earth days. As a result, without direct sunlight, surface temperatures can plummet significantly. This extreme cold is a consequence of the Moon's slow rotation and absence of thermal insulation.