Moon Fact Sheet

For centuries the moon has captivated the inhabitants of Earth. Until science gave them a better understanding of what the moon actually was, philosophers and artists alike made many wild conjectures about the form and function of the moon. Get the real facts below.

What is the moon?

The moon as we know it is the only satellite that currently orbits planet Earth. There are actually hundreds of other satellites or moons in our solar system, of which our moon is the fifth largest. There are many different theories as to how the moon formed and how it ended up orbiting the Earth. The moon makes a complete orbit of the Earth in about a month and has a rotation that is similar in length and speed to the rotation of Earth.

The physical characteristics of the moon

The moon is estimated to weigh approximately 7.3477 × 1022 kg. It has a projected circumference of 10,921 km with a surface area that is equivalent to approximately 7% of the Earth. The majority of the crust of the moon is comprised of silica. Other common elements that contribute to the composition of the moon include alumina, lime, iron and magnesia with trace elements of titanium oxide and sodium oxide. The surface of the moon is covered with craters and "seas" which are actually huge pools of solidified lava.

Moon exploration

Though scientists have conjectured about the moon for centuries, man has only stepped on the moon once in history. The Soviet Union space program was the first to capture pictures of the far side of the moon in 1959. It took ten more years for man to actually step onto the moon, though, and no space program has ever repeated that feat; though robots have collected many other pictures and soil samples since.

Even knowing what we do about the moon, millions of people continue to gaze on the impressive satellite with wonder.