The Moon may seem like a cold and dead rock. But what is the actual temperature on its surface? It varies considerably depending on whether or not sunlight hits it. Temperature fluctuations on the Moon can be extreme.
“Temperatures on the moon range from extremely high to extremely low,” notes John Monnier, a professor of astronomy at the University of Michigan. Temperatures can range from -100°C to over 100°C, he said.
In comparison, the average temperature on Earth is about 15°C, and temperature fluctuations on its surface can range from -89°C to 57°C, according to NASA.
Temperature difference at the same distance
Although the Earth and Moon are at about the same distance from the Sun (about 150 million kilometers), several factors account for the difference in temperature. First, the Earth has an atmosphere that holds heat and maintains a comfortable temperature for life. The Moon, on the other hand, has no atmosphere, so it is exposed to the full heat of the sun.
Earth also has oceans that absorb solar energy and slowly release it at night. The Moon, on the other hand, heats up and cools down quickly because its surface has no ability to retain heat. In addition, a lunar day lasts about 29.5 Earth days, so the temperature on the Moon’s surface is influenced by light and darkness for longer.
The most extreme temperatures in the Solar System
Lunar soil, or regolith, is a good insulator, so it maintains temperature both day and night. However, regolith is not a good conductor of heat. During the Apollo missions, heat flow beneath the surface of the Moon was measured. It turned out that the temperature at a depth of 35 cm was on average 40-45°C higher than the surface temperature, indicating the absence of sharp temperature fluctuations in deeper layers.
According to NASA, temperatures at the Moon’s equator can reach 121°C in sunlight and drop to -133°C at night. After Mercury, the Moon has the most extreme temperatures in the Solar System.
However, the situation is different at the poles of the Moon. There, the sun practically does not rise or set below the horizon, which causes long shadows. These areas, called permanently shaded regions, may contain water ice, an important resource for future missions.
Comfortable place for people
The Lunar Reconnaissance Orbiter (LRO), launched by NASA in 2009, measures the temperature on the Moon using the Diviner thermal imaging camera. In July 2022, LRO found that temperatures remained around 17°C in some shaded pits, making these locations potentially suitable for human shelter.
Double shaded craters
However, some shaded areas of the Moon can reach the lowest temperatures in the Solar System. Craters at the South Pole can be “double-shaded”, which protects them from solar heat and heat reflected from other areas. It is expected that temperatures in such craters could reach 25 K (-248.15°C), or even be colder.
Understanding temperature fluctuations on the Moon is important for future research and possible missions. In order to create equipment that can withstand these extreme temperatures, it is important to understand how these changes affect the equipment.
According to livescience.com
