The Moon's Formation and Origin
Why do the moon’s phases occur?
Interesting facts about the moon
Lunar Eclipses: A Celestial Spectacle
Future Plans for Lunar Exploration
2. Lunar South Pole Exploration
3. Commercial Lunar Exploration
Earth’s moon is the largest and brightest object in our night sky and it's the only natural satellite. The moon influences Earth’s nature, tidal movement and topography. It enables us to thrive by moderating the planet’s wobble on its axis and creating a stable climate. Billions of years ago, a Mars-sized body collided with Earth to form the moon. All things related to the moon are addressed by the adjective “lunar”, derived from the Latin word moon - Luna. This blog explores some more Fun Facts About the Moon.
All theories around the origin and formation of the moon state that it was formed about 4.5 billion years ago, near the time of the solar system’s formation. Much of the moon’s surface changes on a vastly slower timescale than the Earth. Some of the moon origin theories that are both plausible and widely accepted are -
Our understanding of the moon, its atmosphere, composition and origin improved after the Apollo Mission in the 1960s and 1970s. The astronauts of the Apollo missions brought 382 kilograms of lunar samples that pointed to the moon forming from a large impact. The age of the rock samples indicates that the Moon was formed around 60 million years after the solar system began to form. The samples showed that in the early years, the moon was molten and covered with a deep ocean of magma for ten to hundred million years. Such an environment occurs as an aftermath of intensely energetic impact.
Some other things that we learned from the Apollo Moon Rocks are -
The name "Luna" comes from the Latin word for the Moon, and it is deeply rooted in myth and language. In Roman mythology, Luna was the goddess of the Moon, a counterpart to the Greek goddess Selene. The connection between the Moon and the term "Luna" dates back to early civilizations, where the Moon was often personified in stories and legends.
The word "lunar," which describes anything related to the Moon, also originates from this Latin root. Interestingly, many languages use variations of the word "Luna" for the Moon, highlighting the universal significance of this celestial body across different cultures.
To date, there is no evidence to suggest that life, as we know it, exists on the Moon. The harsh environmental conditions, including extreme temperatures, lack of atmosphere, and high levels of radiation, make the Moon an unlikely place for life to thrive.
Although the Moon is inhospitable for life today, it holds the potential for future human colonization. Recent advancements in space technology and lunar exploration have made the idea of establishing a human presence on the Moon more feasible. NASA's Artemis program and private companies are actively researching ways to send astronauts to the Moon and create sustainable habitats.
One of the most exciting discoveries in recent lunar exploration is the presence of water ice at the Moon's poles. Water is crucial for human survival, making the Moon a potential resource for future missions and colonies.
The Moon is about 1/4th the size of Earth, with a diameter of approximately 3,474 kilometers. Its average distance from Earth is about 384,400 kilometers, though this distance varies slightly due to the Moon's elliptical orbit.
The Moon is gradually moving away from Earth at a rate of about 3.8 centimeters per year. While this may seem insignificant, over millions of years, it could have major implications for Earth’s tides and rotational period.
The Moon’s orbit around Earth is not a perfect circle; it is slightly elliptical. This orbit takes about 27.3 days to complete. Interestingly, the Moon rotates on its axis at the same rate it orbits Earth, which means the same side of the Moon always faces us. This phenomenon is called "synchronous rotation."
The phases of the Moon, from new moon to full moon, occur as the Moon orbits Earth. The changing phases are due to the varying angles of sunlight that illuminate the Moon’s surface. These phases have been used for centuries to track time and guide agricultural practices.
Unlike Saturn or Jupiter, the Moon has no rings, and it does not have any moons of its own. Earth's Moon is unique in that sense. While some planets have multiple moons, Earth’s solitary Moon remains an intriguing feature of our planet.
The Moon is believed to have formed around 4.5 billion years ago following a massive collision between Earth and a Mars-sized body, often referred to as Theia. This impact ejected debris into space, which eventually coalesced to form the Moon.
The Giant Impact Hypothesis remains the leading explanation for the Moon’s formation. According to this theory, the collision melted a significant portion of Earth's outer layer, which, after cooling, formed the Moon's crust.
The Moon's interior is divided into three main layers: the core, mantle, and crust.
The Moon’s core is small and mostly composed of iron, with a small amount of sulfur and nickel. The mantle is made up of silicate minerals, and the crust is primarily composed of oxygen and silicon. The Moon's crust varies in thickness, with thicker regions in the highlands and thinner regions in the maria.
The crust’s thickness varies across the Moon. The highlands, which are the lighter-colored regions, have a thicker crust than the dark maria, which were formed by volcanic activity.
The Moon has no active volcanoes today, but there is evidence of ancient volcanic activity. Some regions, such as the maria, were created by volcanic eruptions billions of years ago.
The Moon’s surface is covered with impact craters, dust, and regolith, a layer of loose, fragmented material. These features are the result of millions of years of bombardment by meteoroids.
The Moon's surface is pockmarked with craters of varying sizes. These craters have been formed by meteoroids colliding with the Moon’s surface. Lunar regolith, the fine dust and debris on the Moon, is created by the constant impacts.
The Moon's highlands are mountainous, heavily cratered regions that are primarily composed of light-colored rocks. The maria are large, dark plains that were formed by ancient volcanic eruptions.
For years, the Moon was thought to be completely dry. However, recent missions have confirmed the presence of water, particularly in the form of ice at the lunar poles.
NASA’s Chandrayaan-1 mission and other lunar probes have detected water ice in permanently shadowed craters at the lunar poles. This discovery could be crucial for future lunar exploration, as it could provide a local source of water for astronauts.
Water has also been found to be released from the Moon’s surface during meteor impacts, suggesting that there may be more water beneath the surface than previously thought.
In 2020, NASA's SOFIA telescope discovered water molecules on the Moon’s sunlit surface. This was a groundbreaking finding, showing that water exists even in areas exposed to the Sun's heat.
The Moon does not have a significant atmosphere or magnetic field, which makes it vulnerable to radiation from the Sun and cosmic rays.
The Moon has a very thin exosphere, which is not capable of supporting life. The lack of atmosphere means there is no weather, and the Moon's surface experiences extreme temperature variations.
The Moon's magnetic field is weak compared to Earth’s, but there is evidence that it may have had a stronger magnetic field in the past. Some scientists believe this could have been the result of an early dynamo activity in the Moon’s interior.
The moon has 8 phases -
| Phase | Image | Explanation |
| New |  |
The new moon is completely dark and cannot be seen. |
| Waxing Crescent |  |
It is a thin crescent of light that can be seen to the right from the Northern Hemisphere. |
| First Quarter |  |
It is also called the half-moon |
| Waxing Gibbous |  |
Waxing means that it is getting bigger. Waxing Gibbous is the phase between the half-moon and Full moon |
| Full |  |
The moon is completely illuminated in the Full moon phase. |
| Waxing Gibbous |  |
Waning means getting smaller. The Waning gibbous phase occurs between a full moon and the third Quarter of the moon. |
| Third Quarter |  |
This is also a half-moon, but the opposite half from the first quarter is illuminated here. |
| Waning Crescent |  |
It is a thin crescent of light on the left as can be seen from the Northern Hemisphere. |
From Earth, we always have a view of the same side of the moon, which is the near side of the moon. If you look at the moon in the night sky, every night it will appear to be of a different size and shape or completely invisible. This phenomenon is called the phases of the moon. The view of the moon from Earth changes throughout the month. This happens because the moon does not have its light. When the sunlight reflects off the moon’s surface, it becomes visible to us as the moonlight.
Depending on where the moon is in its orbit around the Earth, the view of the illuminated part of the moon changes each night.
The side of the moon that faces away from Earth is called the far side of the moon. India’s Chandrayaan-3 probe is testing out its landing optics by imaging the far side of the moon. It shows a range of geological features, such as vast impact craters that cast varying degrees of shadows and lunar mare, which are "seas" of cooled moon lava.
A lunar eclipse occurs at the full moon phase when the Earth is positioned between the moon and the sun, and the Earth’s shadow falls upon the moon’s surface.
The moon’s gravitational force is a major influence on the Earth’s tides. When the sun, moon, and Earth are aligned at the time of the new or full moon, the solar tide has an additive effect on the lunar tide, creating spring tides which are extra-high high tides, and very low, low tides. When the sun and moon are at right angles to each other, they cause neap tides, which are moderate.
The successful landing and findings of Chandrayaan II, that too on a modest budget, raised international interest in India’s space exploration potential. As of 30 July 2023, India has launched 431 satellites for 34 countries. The country is tentatively working on a Chandrayaan IV project. Other international projects that international space agencies are working on are -
NASA's Artemis programme aims to establish a sustainable human presence on the Moon by the mid-2020s. They have planned the Artemis III mission with the aim of landing astronauts on the lunar surface, specifically targeting the lunar South Pole by 2025.
There is evidence of water ice on the Moon’s South Pole raising interest in its potential to support future lunar bases and resource exploration for future settlements.
Organisations such as Blue Origin, SpaceX, and Astrobotic and Intuitive Machines are working on many lunar missions such as -
Other than these, there are ongoing international collaborations between the European Space Agency, the Russian Space Agency, and the China National Space Administration among others. The long-term goals are to establish lunar bases, In-Situ Resource Utilisation (ISRU) for extracting water, and preparation for missions to Mars and beyond.
