Moon Unit page header

The Moon is approximately 4.5 billion years old. According to today’s most popular theory, the Moon was created after another planet, about the size of Mars, collided with Earth. The collision sent debris into Earth’s atmosphere which collected, and the Moon was formed.

The lunar orbit is oval shaped, so depending on its point of orbit, the Moon is between 225,740 (perigee) and 251,970 (apogee) miles from Earth. This distance is measured by bouncing laser beams off special reflectors which were left on the lunar surface by the astronauts of the Apollo 11, 14, and 15 missions. Also, the Moon is slowing moving away from Earth at the rate of about 1.5 inches a year.

A lunar day, one rotation of the Moon on its axis, is approximately 27.3 Earth days. Orbit of the Moon around the Earth takes the same amount of time, which is why the view from Earth only shows the same one side of the Moon, what is called the near side of the Moon. The far side is not the “Dark Side of the Moon” since the side of the Moon opposite the Sun is constantly changing. The far side is more cratered and has fewer dark colored areas, or maria, than the near side.

Gravity at the lunar surface is about 1/6 of that on Earth. So, the approximate weights of Edwin "Buzz" Aldrin and Neil Armstrong when they Moonwalked in 1969, were only 27 and 28 pounds. Their 200 pound (Earth weight) spacesuits only added another 33, or so, pounds.

Images seen on the lunar surface are interpreted differently by various cultures. Some of these images are a man’s face, a rabbit, a woman wearing a jewel necklace, a person carrying a burden and accompanied by a dog. Others see a dragon, a skeleton, an angel, a toad and toadstool. These images are created from dark lava formations, maria, Latin for seas, and the lighter colored highlands comprised of anorthosite.

Have you ever taken a stroll at night under enchanted Moonlight? What is this light? Moonlight is actually sunlight reflected from the Moon. Ninety-three percent of the Sun’s light is absorbed by the lunar surface, which then reflects the remaining 7 percent. Earth also reflects sunlight which is called Earthshine. Earthshine can be seen faintly illuminating the Moon when the Sun sets opposite the Earth-facing side of the Moon. This can be seen every 29.5 days.

Due to the Moon’s weak gravity, it has no atmosphere to block any of the Sun’s light or to help trap heat, so temperatures on the Moon’s surface range from extremely hot during the day to extremely cold at night. Daytime temperature on the Moon can reach 253 Fahrenheit (123 Celsius), while at night it can drop to -387 Fahrenheit (-233 Celsius). Only at the north pole and south pole is the temperature constant at -135 Fahrenheit (-93 Celsius).


sources: NASA, Wikipedia






Myths, Facts & Folklore
Roll Over The Moon link to labeled moon page
home page link
calendar pages link
music page link
calendar story link
about POE link

background music control