What Is an Eclipse?

An eclipse takes place when one heavenly body such as a moon or planet moves into the shadow of another heavenly body.
There are two types of eclipses on Earth:

An eclipse of the moon(Lunar Eclipse) and

An eclipse of the sun(Solar Eclipse)

What Is a Lunar Eclipse?

Sometimes Earth moves between the sun and the moon. When this happens, Earth blocks the sunlight that normally is reflected by the moon. (This sunlight is what causes the moon to shine.) Instead of light hitting the moon’s surface, Earth's shadow falls on it. This is an eclipse of the moon -- a lunar eclipse.
A lunar eclipse can occur only when the moon is full.
A lunar eclipse can be seen from Earth at night. There are two types of lunar eclipses: total lunar eclipses and partial lunar eclipses.
A total lunar eclipse occurs when the moon and the sun are on exact opposite sides of Earth. Although the moon is in Earth's shadow, some sunlight reaches the moon. The sunlight passes through Earth's atmosphere, which causes Earth’s atmosphere to filter out most of the blue light. This makes the moon appear red to people on Earth.
A partial lunar eclipse happens when only a part of the moon enters Earth's shadow. In a partial eclipse, Earth's shadow appears very dark on the side of the moon facing Earth. What people see from Earth during a partial lunar eclipse depends on how the sun, Earth and moon are lined up.
A lunar eclipse usually lasts for a few hours. At least two partial lunar eclipses happen every year, but total lunar eclipses are rare. It is safe to look at a lunar eclipse.

Various stages of Lunar Eclipse

What Is a Solar Eclipse?

Sometimes when the moon orbits Earth, it moves between the sun and Earth.When this happens, the moon blocks the light of the sun from reaching Earth. This causes an eclipse of the sun, or solar eclipse. During a solar eclipse, the moon casts a shadow onto Earth.

There are three types of solar eclipses.

Total solar eclipse. A total solar eclipse is only visible from a small area on Earth. The people who see the total eclipse are in the center of the moon’s shadow when it hits Earth. The sky becomes very dark, as if it were night. For a total eclipse to take place, the sun, moon and Earth must be in a direct line.

Partial solar eclipse. This happens when the sun, moon and Earth are not exactly lined up. The sun appears to have a dark shadow on only a small part of its surface.

Annular solar eclipse. An annular eclipse happens when the moon is farthest from Earth. Because the moon is farther away from Earth, it seems smaller. It does not block the entire view of the sun. The moon in front of the sun looks like a dark disk on top of a larger sun-colored disk. This creates what looks like a ring around the moon.

During a solar eclipse, the moon casts two shadows on Earth. The first shadow is called the umbra (UM bruh). This shadow gets smaller as it reaches Earth. It is the dark center of the moon’s shadow. The second shadow is called the penumbra (pe NUM bruh). The penumbra gets larger as it reaches Earth. People standing in the penumbra will see a partial eclipse. People standing in the umbra will see a total eclipse.

Solar eclipses happen once every 18 months. Unlike lunar eclipses, solar eclipses only last for a few minutes.

NEVER look directly at the sun: It can permanently damage your eyes! You must use proper safety equipment to look at any type of solar eclipse.

	Lunar Eclipse	Solar Eclipse
Health risk	Safe to look at moon during eclipse	Retina gets damaged if Sun seen directly with a naked eye
Position of Earth and Moon	Earth lies between the Sun and Moon	Moon lies between Sun and Earth
Types	Penumbral, partial, total or horizontal	Total, annular, hybrid, partial
Occurrence	At night	During day time
Frequency of occurrence	Twice a year or more	A few every year, total being less frequent
Visibility	Moon completely obscured, visible partially or in an orangish hue –visible from all night time places	Sun gets blocked by moon – eclipse visible only in some areas
Duration	A few hours	Usually a few minutes