What shape is the moon why does it appear to change shape?

Answer 1

As the Earth rotates on its axis and the moon revolves around the Earth, we get to see the moon in various different positions with respect to the sun. At any given time, half of the moon is facing the sun, but an observer on the surface of the Earth may only be seeing part of the illuminated surface. The part that is not illuminated is invisible from Earth, so the moon seems to be of different shapes.
The phases of the moon, as viewed from earth, is caused by the angle that light from the sun hits the moon. This slowly changes as the moon orbits the earth and the position of the sun.

Answer 2

It is constantly going around the earth (about 28 days). when the moon is in front of the sun it is called a new moon and we only see the dark side then it goes a quarter of the way around and we see a quarter of it lit then it goes in back of us in relation to the sun and we see it full. Then it moves to the other side and we see the other quarter lit and then it's back to new again.

Answer 3

At first glance they might look similar, but the Moon's phases are caused by seeing various portions of a Moon that is lit on one side. The Lunar Eclipse is cause by the Earth's shadow being cast always on a full moon.

The dramatic difference is that early on in the eclipse shape the Earth's shadow will appear as a dark red bite at the edge of the lunar disk, whereas a waxing or waning gibbous will have a convex shape to the light because the Moon is round and we are seeing the terminator between light and dark.

Later in the Lunar Eclipse the "bite" from the Earth's shadow can resemble the waxing crescent leading to confusion between two phenomenons, but other than during an eclipse the Earth's shadow is not involved in the Moon's phases.

Answer 4

The Moon doesn't look any different than it did 100 years ago.

You're talking about the phases of the moon? That's just a difference in lighting.

Over a few thousand years, there may be a few new craters, but the big wave of intense planetary bombardment that formed most of the big craters was a billion years and more ago. Nothing much changes there now.

WE will change it, of course, when we go there and start building cities...

Answer 5

The moon appears to go through a series of "phases" over a period of 28 days. Starting at a full moon, when it is all lit, it slowly wanes through to a new moon when none of it appears lit. Then it waxes back, as increasing areas of its surface are lit, until it is once more a full moon again.

Answer 6

The moon is an airless rocky body, tectonically quiet, with no atmosphere to cause erosion. Things like craters, and Armstrong's footprints, can last for millions, if not billions, of years. The moon is a static object.

The Earth, on the other hand, is a geologically active world, with volcanoes and tectonic plate movement. She also has a thick atmosphere and liquid water, causing erosion by wind, rain, water, and geologic means, like volcanoes and earthquakes. The surface is always changing. This is why, even though the Earth has been hit by object as often as the moon (in past epochs), there are comparatively few craters visible. The Earth is a dynamic object.In the Earth, there is life and in the moon there is no life because there is no air and it has very rocky surface so no living thing can drink.

Answer 7

Stand with your back to a strong light, and put your hand up in front of your face.
You see all of your hand strongly illuminated, because the strong light shines on it.

Now stand facing the strong light, and put your hand up in front of you. The side of your hand that you see is dark,
because it is the side that the light is NOT shining on.

Stand with your side to the strong light, and hold a round object, such as a tennis ball, up in front of you.
You are looking at half of the illuminated side and half of the dark side. In empty space, you would see
only half of the object; the other half would be completely invisible to you.

The moon goes around the earth every 27.3 days. The only part we can ever see is the part that the sun
shines on, and only as much of THAT as we're in a position to see ... half of it, if it's off to the side of us
like the tennis ball.

Answer 8

The Moon IS always the same shape; it's always round. That it doesn't always LOOK like a sphere is a trick of lighting.

As the Moon goes around the Earth, sometimes we see it only partially illuminated by the Sun, because we generally see only the part that is lit up. (If you look closely, you can see the rest of it dimly illuminated by reflected Earthlight.)

Answer 9

The moon may look different because of the phases it goes through each night. Each day the moon appears different in the sky, until one night you see a full moon.

Answer 10

Because the Moon is orbitting the Earth, about once per month. See link below for more.