Moon Facts

Moon Profile

Diameter:3,475 km
Mass:7.35 × 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
Distance from Earth247,704 Km
Human Visitors24

We look up to the sky every night and see our moon.

Throughout history, various cultures have held beliefs about the moon, from fearing it to thinking it had an effect to change human beings into werewolves!

Our moon is called the “closest celestial body” and is around 384,400 km from Earth.

Phases of the Moon

Earth’s gravity maintains a pull on the moon and its shape is due to its mass being pulled by the gravity to its center.

The view that we see depends on the Earth’s orbit of the Sun, and that casts shadows on the moon to show the eight phases that we are familiar with:  Full Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, Last Quarter, and Waning Crescent.

Size of the Moon

One of the most unique properties of the Moon is that its diameter is over ¼ that of the Earth. There is no other planet in our Solar System that has a moon as large.

While it is larger, the mass of the Moon is rather low for its size due to its low density.

How did the Moon form

One of the theories of the formation of the Moon is that early in the development of Earth, a large body that might have been Mars-sized, hit the Earth and the collision broke off a lot of the crust and mantle from the Earth.

As the materials orbited around Earth, our gravity slowly pulled the material together to form the Moon. This theory may also explain why the Moon’s density is so low because the Earth’s outer crust and mantle are a lot less dense than the interior.

Facts about the Moon

  • The Moon doesn’t have an atmosphere so over many years, each time there was an impact from a meteor or comet, which have left many impact craters that are visible on the surface. Additionally, there is no tectonic activity or any other activity that could affect any resurfacing changes on the craters.
  • We often hear the term “dark side of the Moon,” but both sides of the Moon get the same amount of sunlight. However, the Moon is tidally-locked so that only one side every faces the Earth and since it rotates on an axis taking the same amount of time to orbit the Earth, we never see the other side.
  • The Moon exerts a gravitational pull on the Earth and this causes the Earth to “bulge” and that bulge moves around the oceans with the rotation of the Earth causing low and high tides.
  • Every year our Moon drifts around 3.8 cm away from the Earth. Scientists estimate that it will take around 50 billion years to be far enough away that it takes the Moon 47 days, instead of the current 27.3 days, to complete an orbit around the Earth.
  • The Moon as one sixth of the gravity of Earth. You might notice how this effects people by watching the videos of the astronauts “bounce around” when they are walking on the Moon.
  • Thus far, we have had 12 people that have walked on the Moon: The first was in 1969 when Neil Armstrong was part of the Apollo 11 mission and the last was in 1972 when Gene Cernan was part of the Apollo 17 mission. After 1972 all of the missions to the moon involved unmanned spacecraft.
  • There is hope for more space missions to the Moon. NASA is planning a permanent Moon space station in the near future.
  • We are familiar with Earthquakes, but there are also Moon quakes due to the Earth’s gravitational pull. It causes cracks and ruptures beneath the Moon’s surface.
  • Our Moon is the fifth largest natural satellite in our Solar System.
  • When you look at the Moon at night, many see the “Man in the Moon”. This is just an optical illusion of the light and dark contrasts of the lunar plans and highlands on the surface.
  • The surface of the Moon has about 500,000 craters.
  • There are two kinds of eclipses involving the Moon: a solar eclipse is when the Moon passes between the Earth and the Sun, and a lunar eclipse is when the Earth passes between the Moon and the Sun. The lunar eclipse causes a shadow to be cast on the Moon, a solar eclipse creates a shadow to be projected onto the surface of the Earth.
  • The moon’s diameter is the same distance from Phoenix, Arizona to New York City, New York.

Moon Quiz

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