The moon orbits the earth due to gravity. This gravitational force of attraction between Earth and the moon provides the necessary centripetal force to keep it in a circular orbit around Earth.
The gravitational force of attraction between two objects is directly proportional to the mass of the objects. Earth is bigger and has greater mass than the moon. Thus, Earth exerts a greater gravitational pull on the moon. The moon also has linear speed, and it would continue to move along a straight line if it were not for the gravity of Earth. Earth’s gravity changes this linear motion into circular motion.Learn More
Moon phases occur because the angle of the Earth, moon and sun changes as the moon orbits the Earth. One-half of the moon is always illuminated by the sun. As a person's angle of sight changes, different portions of sunlight and shadow are observed on the moon's surface.Full Answer >
One of the many differences between the Earth and the moon is simply that the Earth is a planet and the moon orbits the Earth as its satellite. The Earth's circumference is 24,873.6 miles, while that of the moon is 6783.5 miles.Full Answer >
The moon orbits around the Earth on a 29 day cycle. Half of the moon is always lit by the sun's rays but different amounts of this illumination can be seen from Earth depending on the angle the moon makes with the sun relative to the Earth.Full Answer >
The most popular theory regarding lunar formation is that a Mars-sized planetoid slammed into the Earth and flung molten debris into orbit around 40 million years after the solar system was created, according to scientists at the National Aeronautics and Space Administration (NASA). This is called the giant impact theory.Full Answer >