A solar eclipse is when the Moon blocks the sun out from people on Earth. We know that the Moon is a thousand times smaller than the sun, so in order to block the sun's light from the people on Earth, all three bodies must be lined up equally. A solar eclipse may not occur even if the Moon, Earth, and the sun are lined up. The distance between the Moon and Earth must be correct. If the Moon looks like the same size as the sun from Earth, then the distance between the Moon and Earth is correct. When the Moon, Earth, and sun are in a straight line, the darker side of the Moon faces Earth. We may only see a solar eclipse when we are on the side of Earth facing the sun.
During a total eclipse, the whole sun is blocked out from the Moon. When a total eclipse starts to occur, the sky starts to darken. The temperature also decreases a few degrees when the eclipse occurs. This happens because the heat from the sunlight decreases.
When the sun, Moon, and Earth don't line up completely, the conclusion is called a partial eclipse. A partial eclipse is when part of the Moon covers the sun, so the rest of the sun is visible. It may seem a little darker, but it is much different when the sky becomes cloudy.
If the Moon is in part of its orbit that is far away from Earth when it passes between Earth and the sun, it is called an annular eclipse. An annular eclipse does not cover exactly the whole sun. During an annular eclipse, a ring of the sun is visible. But the sun's corona, the outer layer of the sun, will not be visible.