How does a solar eclipse occur?
A solar eclipse occurs when the Moon passes directly between the Sun and Earth, temporarily blocking some or all of the Sun’s light from reaching Earth. This can happen only during a new moon, when the Sun, Moon, and Earth are aligned closely enough.
The Moon casts two types of shadows on Earth. The umbra, the darker central shadow, produces a total solar eclipse for places within it, where the Sun can be completely covered. The penumbra, the lighter outer shadow, causes a partial solar eclipse, where only part of the Sun appears blocked. Sometimes the Moon appears slightly smaller than the Sun, leaving a bright ring around it; this is called an annular solar eclipse.
Solar eclipses do not occur every month because the Moon’s orbit is tilted relative to Earth’s orbit around the Sun.
