What causes the Moon to change from a Full Moon to a Half Moon and then to a Crescent Moon ?

Question

Is there ever a period of time when there is no Moon ?

Answer 1

It's the rotation of the moon around the Earth. The Moon is always half-lit by the Sun (i.e. the side facing the Sun is lit, the other side is dark).

Basically, if you draw an imaginary line between the Earth and the Sun, then put the Moon next to the Earth so it lies at a right angle to that line, at this point from the Earth, it looks like a half moon. If the moon is behind the Earth, then it is a full moon, and if the moon is between the Earth and the Sun, it is a new moon. whether you can see these different phases of the Moon depends on where you are on the Earth and where the Moon is in the sky.

The moon is not visible just before a new moon, and the early crescent is notoriously difficult to spot. When the Moon is at the full, it is behind the Earth but can still be seen because space is 3D, so it is slightly above or below the Earth. If it falls into the shadow of the Earth then you get a lunar eclipse - theoretically this should make the moon invisible, but because the Earth's atmosphere bends the light from the Sun, the Moon is usually visible but coloured a coppery red.

Answer 2

Obviously you never paid attention during science class. It's all about the revolution of the planets. When the earth is lined up in a straight line with the sun and moon, there would be no moon. Also depending on the positions, it could cause a full moon, 1/2 moon or crescent moon.

Answer 3

The light you see from the moon is the sun's light reflected by the moons surface. The half moon / crescent is caused by the Earth getting in the way and casting it's shadow on the moon (similar function to an eclipse)

Answer 4

The moon never changes. the shadow on the moon cast by earth is what changes.

A correction on a previous answer, the same face of the moon always faces the earth, not the sun. This is because one revolution of the moon occurs in exactly the same amount of time as 1 rotation

Answer 5

The Moon appears to go through phases. In other words, the amount of the Moon that we can see changes over time in a cyclic period that repeats itself approximately once a month. (The actual period of this cycle is approximately 29.5 Earth days.) The cause of these phases is the relative positions of the Sun, Earth, and Moon. As seen in the diagram, if the Sun is located off to the right of the picture, the Earth and Moon are illuminated as shown (the white areas being the lighted areas). Notice that no matter what phase the Moon is in, HALF of it is ALWAYS lit by the Sun. (Which half is always lit? The half that is facing the Sun.) The reason that we do not always see a Moon which is half lit is because of our position relative to the Moon and the Sun. As the Moon moves in its orbit, different portions of it appear (to us!) to be lit up as we look at it from Earth. This is why we see lunar phases.

Answer 6

The earth's shadow causes the phases of the moon. Every 29 1/2 days there is a new moon and it can't be seen.

Answer 7

The moon's light is simply a reflection of the sun's light, so the degree to which the Earth blocks the sun's light determines how much of the Moon we see, and because the Moon is orbiting the Earth there are times when it disappears below our horizon.

Answer 8

no there is no time where there is no moon, there is just a time when we cant see the moon. the rotation of the Earth causes us to see different parts of the moon.

Answer 9

its got everything to do with the moons rotation around the earth. since the same side of the moon always faces the sun as it rotates around the earth we see the phase shift of the moon

Answer 10

It's how much of the sunny side of the moon we can see at any time, when you can't see the sunny side of the moon this is called a new moon.