Earth is the only natural satellite of the Earth. It is the fifth-largest and most massive satellite in the solar system. Its size is spherical, similar to that of a cricket ball. It doesn't emit light on its own; instead, it shines due to the reflection of sunlight from the Sun.
The distance between Earth and the Moon is approximately 384,000 kilometers. The Moon's gravitational force is one-sixth that of Earth's. It takes about 27 days and 6 hours for the Moon to complete its orbit around Earth, and it takes an additional 27 days to complete one rotation on its axis. This is why the same side of the Moon always faces Earth.
If you were standing on the Moon and looked at Earth, you would see Earth rotating on its axis like a spinning top. However, its position in the sky would remain fixed for years; it wouldn't move from one place to another.
Tides on Earth are caused by the Moon's gravitational force. Due to the Moon's temporary orbital distance, the Sun and Moon appear to be of the same size in the sky. About 59% of the Moon's surface is visible from Earth.
When the Moon passes between the Sun and Earth during its orbit, it completely covers the Sun, resulting in a solar eclipse.
Humans have set foot only on the Moon in space. In 1968, NASA achieved the milestone of sending the first human mission with the Apollo program, and the first human-crewed lunar orbiter mission began with Apollo 8. Between 1969 and 1972, six manned missions landed on the Moon, with Neil Armstrong becoming the first person to set foot on the Moon during Apollo 11. These missions brought back over 380 kg of lunar rock and soil, contributing to understanding the Moon's origin, internal structure, and subsequent geological history. It is believed that the Moon was formed about 4.5 billion years ago after a collision between a large object and Earth.
Since the Apollo 17 mission in 1972, only robotic spacecraft have visited the Moon. Many countries, including India, China, Japan, the United States, and European agencies, have sent missions to study the Moon's surface, water, and ice presence. India's Chandrayaan-1 mission was the first spacecraft from India to orbit the Moon, providing significant insights.
The presence of dark spots on the Moon's surface is due to the presence of millions of craters caused by impacts from asteroids and comets. Approximately 300,000 craters are estimated to be present on the Moon's surface.
Water Presence: The Chandrayaan mission sent by India in 2008 provided evidence of water and ice on the Moon's surface. This finding was later confirmed by NASA.
The Moon's Origin: About billions of years ago, a collision between a large object and Earth resulted in the Moon's birth. Research on lunar rock samples brought back by Apollo missions supports this theory.
The Moon's presence is integral to Earth's dynamics and has played a role in shaping Earth's history. It continues to intrigue scientists and space agencies worldwide, contributing to our understanding of the universe and our place within it.
