Have you ever been playing outside in the late afternoon and stopped to stare up into the sky? From time to time, you’ve probably noticed that sometimes you can see the Moon during the day. Have you ever thought this was odd, since usually the Moon can only be seen at night?
You probably already know that the Moon is not a star. In other words, it’s not a miniature version of the Sun. The Moon produces no light of its own like the Sun does. Instead, we see the Moon because of the Sun’s light it reflects back to our eyes.
In fact, the Moon reflects so much of the Sun’s light that it’s the second brightest object in the sky after the Sun. Even though it’s not even close to as bright as the Sun, the Moon is still 100,000 times brighter than the next brightest nighttime star!
The Moon is also big and much closer to the Earth than the nearest celestial objects in the sky. Given its size and nearness to Earth, it’s easy to see why the Moon can be seen so easily at night. That also explains, though, why we can sometimes even see it during the day.
Usually, the Sun’s light is so bright that it makes it impossible to see less bright, far away objects in the sky. These objects — other planets and stars — can usually only be seen at night when the Sun’s light doesn’t outshine them. They’re still there. You just can’t see them with the naked eye, because the Sun’s bright light is all you can see.
The Moon, though, is so big and so bright and so close to the Earth, that it can sometimes be seen even during the day. The Moon is not always in the same place in the sky all the time. During the lunar cycle, the Moon is sometimes closer to the Sun and sometimes farther away from the Sun.
When the Moon approaches its New Moon phase, it’s closest to the Sun and can be seen more easily during the day, because it reflects even more of the Sun’s light back to Earth.