Moon

Moon

The Moon is the natural satellite of the Earth whose name is sometimes used, par excellence and with the lowercase initial (“a moon”), as a synonym of satellite also for celestial bodies that orbit around other planets.
The Moon orbits at an average distance of about 384,400 km from Earth, close enough to be observable with the naked eye, so that on its surface it is possible to distinguish dark spots and light spots. The first, called seas, are almost flat regions covered by basaltic rocks and dark-colored debris. The light lunar regions, called high lands or plateaus, are several kilometers higher than the seas and have reliefs up to 8000-9000 meters high. Being in synchronous rotation, it always turns the same face towards the Earth and its hidden side remained unknown until the period of space exploration.

Astronomical Observation –
Observing the Moon is a fascinating activity accessible to all astronomy enthusiasts, both beginners and experts.
The Moon can be observed at virtually any time of the night, but is particularly impressive during the full moon phase, when it appears fully illuminated. However, during the waxing or waning phases, it is possible to observe interesting details along the terminator, the border line between the illuminated and shadowed parts.
Identifying the position of the Moon in the sky is obviously one of the easiest activities. It can also be done using specific apps or websites that provide information on the position of celestial bodies based on your location and the current time.
You can observe the Moon with the naked eye, but if you want to examine its details, binoculars or a telescope are better tools. A telescope with good magnification will allow you to see craters, mountains and valleys on the lunar surface.
Looking carefully at the surface of the Moon you will notice many interesting features, such as craters, lunar seas (basaltic plains), mountain ranges and canyons. Color variations on the surface can also be observed, which may be caused by differences in soil composition.
If you have a suitable camera, you can take photos of the Moon. In this way you can obtain, by trial and error, surprising images of surface details.
Over the course of the night, you will notice that the position and appearance of the Moon changes slightly. This is due to its motion of revolution around the Earth.
Astronomical observation, even of the Moon, requires practice and patience. Don’t expect to see all the details at first glance. You have to spend time examining the Moon to enjoy the experience.
Always remember to observe the Moon in a dark place free of light pollution to get the best possible experience.

Physical characteristics –
During its orbital motion, the different appearance caused by the orientation with respect to the Sun generates clearly visible phases which have influenced man’s behavior since ancient times. Personified by the Greeks in the goddess Selene, she was long ago considered influential on harvests, famines and fertility. She influences the life on Earth of many living species, regulating their reproductive cycle and hunting periods; she acts on the tides and the stability of the earth’s rotation axis.
According to astronomical and geological theories, the Moon is thought to have formed 4.5 billion years ago, not long after the birth of the Earth. There are several theories regarding its formation; the most accepted is that it was formed by the aggregation of debris left in orbit after the collision between the Earth and a Mars-sized object called Theia.
The visible side of the Moon is characterized by the presence of approximately 300,000 impact craters (counting those with a diameter of at least 1 km). The largest lunar crater is the South Pole-Aitken basin, which has a diameter of about 2500 km, is 13 km deep and occupies the southern part of the hidden face.
The Moon has a diameter of about 3,474 kilometers, about a quarter of that of Earth. It is the fifth largest natural satellite in the solar system.
The lunar surface, as mentioned, is mainly made up of rocks and dust, with impact craters, mountains, valleys and seas. Seas are relatively flat plains formed by solidified lava flows.
Gravity on the Moon is about one-sixth that of Earth, meaning that objects on its surface weigh about one-sixth as much as they would on Earth.
The Moon has an extremely thin atmosphere, composed mainly of trace gases such as helium, neon and argon. This atmosphere is so thin that it can support neither air nor liquid water.
The surface temperature of the Moon can vary greatly. During the lunar day, it can reach up to around 127°C (261°F) in sunlit areas, while in shaded areas it can drop to -173°C (-280°F).
The Moon takes the same time to rotate around the Earth (about 27.3 Earth days) as it does to complete one revolution around the Earth (about 27.3 Earth days). This phenomenon, known as synchronous rotation, means it always shows the same face to the Earth.

Space missions –
Space missions to the Moon have a rich and fascinating history, which began in 1959 with the Soviet Union and the United States of America launching the first lunar probes. Here is an overview of major space missions to the Moon:
– Soviet Union Moon Program: Luna 2, launched in 1959, was the first probe to reach the Moon and impact its surface. In 1966, Luna 9 was the first probe to land on the Moon and transmit images from its surface. Subsequently, the program continued with orbiter and lander missions, but none of the Soviet probes ever landed a human crew on the Moon.
– United States Apollo Program: The Apollo program, which began in 1961, was a United States effort to put a man on the Moon. In 1969, the Apollo 11 mission saw Neil Armstrong and Buzz Aldrin walk on the Moon, followed by six more Apollo missions that put men on the lunar surface until 1972.
– Lunokhod program of the Soviet Union: This program included missions with remotely controlled lunar rovers. Lunokhod 1, launched in 1970, was the first rover to explore the Moon, followed by Lunokhod 2 in 1973.
– United States Lunar Reconnaissance Orbiter (LRO) program: Launched in 2009, LRO is a satellite orbiting the Moon that has mapped its surface in great detail, helping to identify sites of possible interest for future human missions and to study the lunar environment.
– Chinese programs: China has undertaken several lunar missions in recent years. In 2013, it successfully sent the Yutu rover to the Moon as part of the Chang’e 3 mission. In 2019, Chang’e 4 became the first mission to land on the far side of the Moon, also carrying a rover. China has planned further missions, including building a lunar space station.
– Private programs: Since the 2000s, several private companies, including SpaceX and Blue Origin, have expressed interest in lunar missions. SpaceX has announced its Artemis program, aiming to put humans on the Moon in the near future.
These are just a few of the major space missions to the Moon, but there have been numerous other missions and programs that have contributed to our understanding of our natural satellite and set the stage for future exploration.

Guido Bissanti