the day and night cycle
After watching the skies for thousands of years, we’ve learned a good bit about the Sun. We don’t know everything about it, but we do know that no matter where we are on Earth, the Sun appears in the eastern sky at the beginning of the day. The Sun then seems to rise over our heads in a wide arc. At noon, it seems to be right above our heads, at a place in the sky called the zenith. Then it seems to fall back down slowly through the western sky, until it finally sets, or disappears under the horizon. The horizon is the point where, as far as we can see, the sky touches the ground or the ocean, depending on where you’re looking.
We also know that as sure as the Sun seems to set in the west at the end of every day, it rises in the east to start the next day. We can guess that the Sun continues to travel under the horizon, from the western sky back to the east, even though we can’t see what’s happening without help from technology.
view From the Sun
Using technology, like rockets and satellites, we can send cameras into space to take pictures and video of the Sun. We can take pictures and video of the Earth, too. We can even see what the Earth looks like from the Sun’s point of view. We can see that the Earth is actually the one moving each day. From space, the Earth looks like a ball that constantly turns from west to east, or counter-clockwise. We get carried along for the ride, even though we don’t usually notice it.
When the spot where you are faces the Sun, it is day. When you turn out of the Sun’s light, it is night.