* The moon: We don't always see a full moon in the daytime because the moon's phases are determined by how much of its sunlit side is facing Earth. During the day, you might see a crescent moon, a gibbous moon, or even a thin sliver. This is because the moon is still reflecting sunlight, even if it's not fully illuminated from our perspective on Earth.
* The Sun: The sun *always* appears full from Earth, regardless of the time of day. It's only during a solar eclipse that we see a partial or total obscuring of the sun.
So, why does the moon look different in the daytime?
It's all about the angle of the sunlight hitting the moon. When the moon is in the daytime sky, it's usually not positioned directly opposite the sun. This means the sun is hitting the moon at an angle, illuminating only part of its surface.
Think of it this way: Imagine holding a ball in the sunlight. If you hold it directly facing the sun, you'll see the entire ball illuminated. If you hold it at an angle, you'll only see part of the ball lit up. This is the same principle that applies to the moon in the daytime.
In short: The moon can appear in various phases during the day, but it's always a full moon when it's fully illuminated by the sun. The sun always appears full from Earth, unless there's a solar eclipse.
