The earth has only one natural satellite called moon. It is also called dead satellite.
Moon’s gravity is just 1/6 of earth’s gravity. It is only 1.62m/s².
A large size terrestrial body collide with earth 4.53 billion years ago and a large piece of earth is separate and revolve in orbit around earth. Now that large piece is our moon.
Due to moon’s less gravity, there is no atmosphere on the moon because the escape velocity of atmospheric particle is greater than the escape velocity of moon and due to this the atmospheric particle escape out of moon’s gravitational pull.
Moon’s escape velocity is only 2.38km/sec while earth’ escape velocity is 11.19km/sec.
Moon complete one revolution of earth in just 29.4 days While earth can complete one revolution of sun in 365.25 days.
Moon can complete one revoution on its axis in 27.3 days.
Earth’s one day time 23 hours and 56 minutes. This is the cause of leap year.
According to some theories if moon does not exist then earth’s day time would be approximately 6 to 10 hours. So moon increase earth’s day time.
Moon’ gravity cause tides in sea.
Thousands of asteroid and comets was collides with moon’s surface and cause craters on its surface. You can see these craters from earth by telescope.
The first living animal land on the moon surface was a dog name Laika on 3 November 1957.
And The man who took the first steps on the moon’s surface on july 20, 1969, was named Neil Armstrong .
Neil Armstrong and aldrin walked on surface of the moon.
Radius of the moon is approximately 1,738 km Earth to moon distance is 384400kms.
Light can take 1.2 second to reach the moon from earth.