Moon is widely known as the only satellite for Earth, and it is quite old - 4.6 billion years (which is approximately 50 million years after the creation of our solar system). Moon is always faced with the same side to the Earth, as both of them are moving synchronically. The first human made landing on the Moon was in 1969 by Apollo 11, and the first mission on the Moon in general was made by Soviet Union in 1959.
Moon Characteristics
- Diameter 3,475 km- Mass: 7.35 x 10^22 kg (0.01 Earths)
- Orbits: The Earth
- Orbit Distance: 384,400 km
- Orbit Period: 27.3 days
- Surface Temperature: -233 to 123 °C
- The dark side of the Moon doesn't exist
Indeed, both sides of the Moon get similar amount of sunlight, but on Earth it is possible to see only one side of the Moon. It can be explained because the Moon moves around its own axis as long as it orbits Earth, so we can observe only one side of the Moon all the time. The only possibility to see the other part of the Moon is to look at it from spaceship.
The Moon controls the levels of tides on Earth
The gravitational pull provided by the Moon created two bulges in Earth. The first faces the moon directly, and the second doesn't face the Moon and is situated on the opposite side. Earth rotates and the bulges move as well, and gravitational pull of the Moon influences increasing or decreasing of the tides all over the world.
The Moon is moving away from Earth
Every year the Moon is 3.8 cm farther from Earth. According to calculations, if the Moon will do so during next 50 billion year, by this time it would take 47 days for the Moon to make full circle around Earth. Now it is a little bit more than 27 days.
A human weight is way less at the Moon
Earth has stronger gravity than the Moon, as the mass of Earth is bigger, so at the Moon you will probably weigh about 1/6 (16.5%) of your usual (Earth) weigh. It is the reason why astronauts on the Moon can make such great and high jumps.
Only 12 people have ever walked on the Moon, all of them are from USA.
The first person on the Moon was Neil Armstrong in 1969 during the Apollo 11 mission. The last human to walk the Moon as for now is Gene Cernan, in 1972 during the Apollo 17 mission. After 1972 only non-human vehicles landed on the Moon.
Atmosphere on the Moon doesn't exist
It implicates that the Moon's surface is defenseless when it comes to cosmic rays, meteorites, other space objects and solar winds. Due to this fact the Moon has drastic variations of temperature. The Moon sky is constantly black and sounds there can't exist.
The Moonquakes are real
Our planet has gravitational pull as well and it influences the Moon. The astronauts used seismographs during their missions on the Moon and detected small quakes just few km under the surface, which created small cracks. Some researchers believe that Moon has similar to Earth molten core.
The first spaceship to arrive at the Moon was Luna 1 (1959)
Soviet Union launched this spaceship. It went through 5995 km of the Moon's surface and then moved into orbit around the Sun.
The Moon is top-5 biggest satellite in our Solar System
The Moon is 3.475 km in diameter, and is way smaller than other moons of Saturn or Jupiter for example. Earth is 80 times bigger than the Moon, however, the age of both is approximately similar. There is a probable theory that Moon used to be the part of Earth, but then something ran into Earth on its very first period of life and the Moon appeared.