Unlike other planets, the Earth has only one moon, which is one of the biggest natural satellites in the solar system.
Other than giving us a beautiful light in the evening, there are many fascinating and mind-blowing facts about the Moon that you should know. Why do the moon and the high tide make sense? Do we have a real “sister moon”? Or is the moon actually a planet? So stick around and click on this gallery to find them all out!
The Moon is the Earth’s only natural satellite and was formed 4.6 billion years ago, not long after the Earth was formed. The Moon rotates in sychronization with Earth, and that means it keeps the same side facing the Earth.
The first unmanned mission to the Moon was in 1959 by Russia’s Soviet Lunar Program, while the first manned exploration of the Moon was in 1969 done by the NASA in the United States.
The Moon, Earth’s Nearest Neighbor
Since we can see it in the night sky by our naked eye, the Moon is our closest astronomical neighbor. At the Moon’s extreme perigee — or its closest approach to the Earth — it comes as close as 356,400 kilometers. On the other hand, the Moon’s extreme apogee — or the farthest distance it can get from the Earth — goes as far as 406,700 kilometers.
A violent collision created the Moon
There have been several hypotheses as to how the Moon began to exist, but the most popular and accepted theory is that the Moon was formed from the debris out of a collision between the Earth and Theia, a planet (or rock) about the size of Mars.
Making of the Moon
According to a famous theory, about 4.5 billion years ago the Earth and the theorized planet (or rock) Theia collided against each other. This created a bunch of smaller debris that surrounded around the planet, then these debris joined together and formed a spherical object what we see today as the Moon.
The Moon keeps the same side towards Earth
Very long ago, the Earth’s gravitational influence slowed down the rotation period of the moon to match its orbital period, and this effect had stuck ever since. Other moons that surround the other planets also show the same kind of behavior.
A person would weigh much less on the Moon
Because of the Moon’s very much smaller mass compared to the Earth’s, the effect is weaker gravity. So it means once you’re on the Moon, you will feel definitely lighter — about 1/6 of your weight here on Earth. That explains why astronauts could leap and bound very high in the air.
Earth’s Sister Moon
It’s a common knowledge that the Moon is the only natural satellite here on Earth. However, there is another satellite around the earth called Cruithne, which is incorrectly referred to as a “sister moon.” It was discovered by scientists in 1999, and named after the ancient people of Ireland, Cruthin.
Cruithne is a three-mile asteroid that is situatied on the Earth’s gravitational scope, therefore making as a satellite to our planet. The asteroid takes 770 years to complete its bean-shaped orbit around the Earth, which describes as a horseshoe orbit. According to many scientists, the orbit will stay that way around Earth for at least 5,000 years.
While earthquakes are caused by the sudden movement of the Earth’s crust, moonquakes are otherwise caused by the Earth’s gravitational pull. Astronauts who have landed on the moon used seismographs which recorded small moonquakes. They occur several kilometers under the surface, which leads to small cracks and fissures on it. Scientists believe that the Moon also has a molten core like the Earth.
Solar eclipses will become more difficult to achieve
In a few million years we will see no more solar eclipses. It is because the moon the moon is slowly drifting farther away from the Earth. This will become so distant that in about 500 million years the Moon will appear smaller than it does now, rendering it impossible to “eclipse” the Sun.
The Moon has only been walked on by 12 people
All of these 12 people are American male astronauts, who made a successful step into the moon. They are, in chronological order: Neil Armstrong (1969), Buzz Aldrin (1969), Charles “Pete” Conrad (1969), Alan Bean (1969), Alan Shepard (1971), Ed Mitchell (1971), David Scott (1971), James Irwin (1971), John W. Young (1972), Charles Duke (1972), Eugene Cernan (1972) and Harrison Schmitt (1972).
The Moon has no atmosphere
Unlike the Earth, the Moon has no air to breathe and no wind — that’s why the flags planted by the lunar astronauts never flutter and otherwise stay stiff. Because the moon is considered to have no atmosphere, it cannot protect itself from solar winds, meteorites, and cosmic rays. You hear no sound on the moon, and the sky always look pitch-dark because of the utter lack of atmosphere.
There is a very little thin layer of gases on the moon’s surface, which resembles an atmosphere (but not quite). It’s called an exosphere.
The first spacecraft to reach the Moon
The first spacecraft to successfully land on the Moon was a robotic spacecraft called Luna 2, on September 14, 1959. Luna 2 was also the first man-made object to land on another celestial body.
The Moon Is a Planet?
The Moon is bigger compared to Pluto, and is also one-quarter the Earth’s size. So this leads many people to ask if the Moon is also considered a planet.
Many scientists do think the Moon as also a planet, and some refer to the system of the Earth and the Moon as a “double planet,” like Pluto and its moon (and biggest satellite) Charon.
Moon is the fifth largest natural satellite in the Solar System
The Moon’s diameter is 3,475 kilomenters, trailing behind the much bigger major moons of Jupiter and Saturn. While the Earth and the Moon is about the same age — 4.5 to 4.6 billion years — the Earth is otherwise about 80 times the Moon’s volume.
You may wonder why there are tides. It’s because of the Moon’s gravitational influence on the Earth which is so strong that it causes the ocean water to “bulge.” As the moon orbits the Earth and the Earth also rotates, the bulge also moves. The parts of the Earth where there is a bulging, experience a high tide, while other areas are prone to a low tide.
When there are no other forces present, the Earth rotates on its own axis. In this manner, the ocean water is maintained at equal levels around it by its own gravity pulling inward and the centrifugal force (or inertia) pushing outward.
Although we know about the gravitational pulls between the moon and the earth, and the sun and earth that influence the tides, it’s the moon that dictates most of them.