Why does the moon seem to change shape week to week?

Answer 1

One day on the moon is equal to a month on earth. This is because one of the moon's orbits around earth is the same as one rotation of the moon on its axis. So when we see the phases of the moon change, we are actually seeing a day slowly unfolding and coming to an end on the moon's surface. This explanation would have to be modified if the moon turned more rapidly on its axis, but that wouldn't change the moon's phases as we see them. Another explanation for the phases of the moon is to think of the angle that is formed by these three points: sun, earth and moon. We would call this the sun-object angle of the moon. Earth is always the point at which the angle is measured. During a total solar eclipse, the moon is totally dark and the angle is zero, and during a total lunar eclipse the moon is at full phase and the angle is 180 degrees. As the moon orbits the earth over the course of a month, this angle changes, and it describes the amount of the moon's surface that will appear illuminated to us on earth.

Answer 2

Phases.

As the moon orbits the earth over the course of a lunar month (about 28 days), we see it full when it is opposite the sun from us, and new when it is between the sun and us. It waxes and wanes between those two states. If you observe Venus through a telescope powerful enough to resolve the disk, you will notice it too is in phase. Even at half phase (half full) it is still quite bright. We cannot see Venus in full phase because then it would be on the other side of the sun, in our day light. You might be able to see that if you knew right where to point your telescope. Mars, Jupiter, Saturn--these all appear nearly full to us all the time because they are always further from the sun than we are, and we see them in our night sky.

Answer 3

Because earth rotates in ancircular motion. If the sun is on one end and when we face the sun itLIGHT when we face the MOON its dark.

Put another way, the moon is moving around the earth. When the moon is on the same side as the sun, the sun shines on its back so we can't see it. When the moon is on the opposite side from the sun, the son shines on its front so we can see it. The changes of the moon happen as more and more (and then less and less) of the part we can see has the sun shining on it.

The same reason accounts for why moonrise changes from day to day. When the moon is on the same side as the sun (that's what we call new moon), it rises and sets at the same time as the sun because it's in the same part of the sky. When it's on the opposite side (what we call full moon), the moon rises when the sun sets and vice versa.

Answer 4

The Moon changing in the course of each month is due to The Moon's rotation around the Earth and the Earth's rotation around the Sun.

When the Moon travels around the Earth (depending on where the sunlight is pointing to) the Moon goes through phases, which is just different positions of the moon as the Sunlight is hitting it.

There is new moon, cresent, half moon, gibbious, and then a full moon. (Either waxing or wining.)

Answer 5

Because the moon is in orbit around the earth and the sun is shining on a certain point of the moon. We can see the changes from our perspective. This is similar to a shadow. Sometimes we can only see a sliver of the moon because the sun is almost directly facing the moon and we can't see that side.

Answer 6

I don't have an account, or I would improve the question to make it make more sense. Its meaning can be interpreted though and I have answered it accordingly

Moonlight is simply reflected sunlight. The moon orbits earth, and only half of the moon is facing the sun at one time. However, the perspective is different to viewers on earth, giving the illusion of a circle which wanes into a crescent and then to nothingness, but soon reappears on the other side and waxes into a full circle again.

Answer 7

it changes from a full circle than it changes in a month into a solar eclipse

Answer 8

The Moon's shape doesn't change - it remains more or less spherical. What changes is what part of the Moon, of the side turned towards us, is illuminated by the Sun.

Answer 9

The Moon rotates around the Earth, and the light of the Sun only shows which side the Moon turns.