The Moon is approximately 384,400 km (239,000 miles) from the Earth.
A radio signal from the Earth and bounced off the Moon's surface back to Earth would take approximately 2 seconds. Communication with an astronaut on the Moon would thus have a several second pause between a question and an answer.
SizeThe diameter of the Moon is 3479 kilometers (2162 miles). This is about 1/4 the diameter of the Earth (12,756 kilometers or 7,926 miles).
MassThe mass of the Moon is 7.35*1022 kilograms, which is about 1/80 of the mass of the Earth. (1022 is 10 times itself 21 times or 1 followed by 22 zeros.)
DensityThe density of the Moon is 3340 kg/m3.
Density problemCan you verify the density of the Moon?Density = mass divided by volume, d = m/V.The volume of a sphere = 4/3 times pi times its radius cubed,The average temperature on the surface of the Moon during the day is 107°C. That is hot enough to boil water on the Earth. During the night, the average temperature drops to −153°C.
MotionThe Moon revolves around the Earth in an elliptical orbit every 27.3 days. The same side of the Moon always faces the Earth. Due to the angle of the Sun on the Moon, we see different portions of Moon illuminated. These are called the phases of the Moon.
GravityBecause of its smaller size and mass, the gravity of the Moon is about 1/6 the gravity on the Earth. That means that a person who weighs 180 pounds on Earth would only weigh 30 pounds, if measured on the Moon. That is why when the astronauts were on the Moon, they were able to jump so high—even while wearing the heavy space suit.
Moon causes tidesThe force of gravity from the Moon affects the Earth. Its gravity reaches the Earth and pulls the oceans toward the Moon, causing the tides. The gravity from the Sun also affects the tides. The highest tides will always occur when the Moon and Sun are aligned. That is when there is a New Moon or a Full Moon.
