In some afternoons we see both the sun and moon on the sky. Exposed to sun directly, why moon is not full?

Question

Some days in the afternoons, when you observe the sky, you see the bright sun and faded moon. It is clear that the moon is directly exposed to the sun, but still only three fourth or less of moon is seen. When exposed to sun directly, I believe the faded moon needs to be full round, since the whole moon is exposed to sun. Why it is not a full moon at that time?

Answer 1

Next time you see this, try this simple experiment. Take a white ball and hold it up next to the Moon. You'll see that the white ball is illuminated in exactly the same way as the Moon, because both are spheres lit by the same light source (the Sun). The Sun is so far away that the difference in distance between the ball and the Moon is irrelevant.

Answer 2

Thje moon is closer to the earth than the sun is. So when you see the sun and moon close together in the sky a few days after new moon, the sun is BEHIND the moon, and most of the sunlight falls on the far side, with only a thin crescent of light visible to earth.

As the month progresses and the moon moves around the earth, you'll see the distance between the sun and moon in the sky increase. As the moon gets further west of the sun, more of the moon's visible surface is facing the sun, and hence the moon "waxes"

At a full moon, the moon rises just as the sun is setting. Moon and sun are now on opposite sides of the earth, and NOW the whole near side of the moon is exposed to the sun. During the night, when we look up at a full moon, the sun is behind us (on the other side of the earth) but it is shining directly on the moon.

Answer 3

The people on the other side of the Earth cannot see the moon when you do. Yes, you can see the sun and the moon at the same time during the day. You just have to know where to look for the moon. The moon was new at 5:01 am central daylight time on August 20. Every day the moon gets farther from the sun as the moon rotates around the Earth. The moon moves east along its orbit its own width in about 40 minutes, which means it can be be above the horizon in one location for almost 15 hours. The phase of the moon is the same at the same time for every one on Earth, taking into account time zone differences. When you can see the moon, people on the other side of Earth cannot see the moon until the Earth rotates around enough so that the moon will rise and go across the sky and set.

Answer 4

It is clear , if you see both the sun and the moon at the same time that means not all the half moon sphere facing the earth is exposed to the sun rays.As the angle between the sun and the moon increases -with the earth as the angle node- the part of the half moon sphere facing the earth becomes bigger and the part of the moon you sea increases.

Answer 5

It has to do with relative distance from the sun, with relationship to the Earth, and where you are.

The moon is an object in the universe, but it faces the Sun. The part you see is reflecting light, the dark area appears to be "hidden" and therefore you only see part of the moon.

Also the moons face you see NEVER changes. It's ALWAYS the same. The moon is facing the earth at the same place every time.

Its like an invisible string attached to a tennis ball, the part where the string attaches is the part that is pulled by the string, so the ball never really rotates.

Answer 6

The moon is not full because its not in opposition which means the sun will be setting and the moon is rising at the same time. In other words, if the angle of the (moon/sun) is not near 180 degrees the surface will only partially be lit when both the sun and moon are in the same sky.

Answer 7

Because when the sun and moon are visible at the same time, the light from the sun is coming to the moon from its side, relative to our viewpoint on the Earth. You see only the side that is illuminated.

When the moon is full, the light from the sun is coming to the moon from the front, relative to our viewpoint on the Earth. You see the whole front that is illuminated.

Answer 8

In other words, the sun shines on only half the moon, like it shines on only half the Earth. But sometimes, part of the side that is sunlit is not facing the Earth. Most of the time, in fact. It's times like that when we see less than full moon.

Answer 9

the reason that we dont see a full moon is that the other side of the moon is exposed to the sun, the side we see isnt. in other words, it would be casting a shadow. the reason you see part of it is it is not directly in te sunlight.

Answer 10

One simple example to understand this phenomena

Suppose 3 guys are standing in a line and facing straight to the North,
The last person can see middle person but not 1st guy. If the middle guy moves one step on his side, the last person can see 1st person partially.
Now if the middle guy turns and faces East. He can see both 1st guy and last guy on his sides.

In this situation u r the middle person, Sun is the last guy and moon is the 1st guy. Since Sun can see moon partially, that partial part is visible and rest part are masked by earth's shadow.

It is important to note that Earth shadow is not narrow. it is conical. So the shadow is bigger than earth's size.