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Moon fun facts

As the Earth travels around the Sun, it is accompanied by its nearest neighbor in space, the Moon. The Moon is called the Earth's satellite, and revolves around the Earth in a definite, regular path called the Moon's orbit.

Moon fun facts - crater Langrenus Moon fun facts - What the Earth looks

Moon fun facts

A photograph of the crater Langrenus from the Apollo 8 spacecraft. This crater is 85 miles in diameter

What the Earth looks like from the Moon. In the foreground is the Moon's barren surface. The surface of the Earth is obscured by a layer of cloud. This photograph was taken from Apollo 8

The Moon is held in its orbit by the gravitational attraction of the Earth. This was first explained by the great scientist Sir Isaac Newton (1642-1727). He knew that every object attracted every other object. He explained how this force of attraction (the force of gravity) keeps the planets revolving in their orbits around the Sun and the Moon in its orbit around the Earth.

The Moon is about a quarter the size of the Earth in diameter, and its weight is about one-eightieth that of the Earth. Astronomers know a great deal about the Moon. It is bleak, and has no air or water. It has a hard surface, partly covered with dust and pitted with craters. It has great, dry plains, known as maria, or seas, and towering, jagged mountains. On the Moon, days are extremely hot and nights extremely cold. In the 1960s, our knowledge of the Moon greatly increased. Space probes and manned flights brought back much information. On July 20, 1969, Neil Armstrong and Edwin Aldrin were the first men to walk on the Moon. They and the astronauts of Apollo 12, which landed on the Moon on November 19, 1969, brought back samples of rocks which showed that the Moon is probably as old as the Earth. The danger of manned flights to the Moon was, however, demonstrated in April 1970 when Apollo 13 was forced to abandon a landing after an explosion in the service module.

Moon fun facts - Phases Moon fun facts - movement

Moon fun facts

Phases of the Moon. We only see the part of the Moon which is illuminated by the Sun. When the Moon is between the Earth and the Sun none of the illuminated side can be seen from the Earth (new Moon). When the Moon is at the other side of the Earth the whole of the illuminated side can be seen (full Moon). Between these two positions we see part of the illuminated side

Owing to its slight wobbling movement it is possible to see around alternate “edges” of the Moon

Moon fact: the planet's orbit round the Earth is not quite circular. It is elliptical (oval). As a result, the Moon is nearer the Earth at some times than it is at others. When the Moon is near the Earth, it travels faster along its orbit than when it is farther away. Its average speed is about 2,300 miles an hour.

The average distance of the Moon from the Earth is about 239,000 miles. In space, this is a short distance. A rocket that took a day to travel from the Earth to the Moon, would take a year to reach the Sun, traveling at the same speed.

Because the Moon is near the Earth, it appears to us to be much bigger than the stars. In fact, the stars and all the planets are bigger than the Moon, some of them millions of times bigger.

The Moon takes 27 days and 8 hours to travel around the Earth. It also takes exactly the same time to rotate once upon its own axis. As a result, the same part of the Moon's surface is always turned towards the Earth. Our first knowledge of what the other side of the Moon looks like came in 1959 when the Russian space-probe Lunik 3 transmitted photographs of the hidden side back to Earth. All of the Moon has now been mapped by lunar orbiter probes. Apart from the great Mare Orientalis, the far side of the Moon lacks the maria that are a feature of the side we can see.

Moon fun facts - side of the Moon Moon fun facts - side of the Moon

Moon fun facts

This picture of the far side of the Moon is based on photographs taken by the Russian automatic interplanetary station, Lunik 3

The side of the Moon which faces the Earth

The Moon has no light of its own. The silvery moonlight which has inspired poets, painters, and musicians, is really light from the Sun which is reflected by the Moon's surface.

As the Moon moves around the Earth, different portions of its surface receive the sunlight. This causes it to appear to us almost as though the Moon changes its shape as the month goes on. We call these 'changes' the phases of the Moon. The phases range from New Moon (when the Moon is not visible at all), through First Quarter (half illuminated) to Full Moon (whole disc illuminated). From Full Moon the sunlit part of the disc turned towards us gradually shrinks, through Last Quarter (half illuminated) to New Moon again.

The craters or ring formations on the Moon's surface range from vast mountain-encircled plains, up to 150 miles across, to tiny pits only two or three feet across. The largest craters can be seen with good binoculars, but the smallest crater pits can be detected only on the photographs brought back by astronauts or transmitted back by space probes.

Some of the craters have bright streaks radiating from them called ray systems. These can be seen most easily at Full Moon. Astronomers do not know what causes them. The great plains (maria) have very few large craters, and are dark in color compared with the mountainous areas

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