An eclipse occurs when a celestial object such as moon moves directly into the shadow of another celestial object. For example, during a solar eclipse the moon comes between the earth and the sun due to which the sun was blocked for a brief period of time and people on Earth cannot see it.
In ancient times, during solar eclipse people were frightened by seeing that light of the sun was partly or completely hidden. They thought of various reasons for these natural phenomenon which were not scientific.
Today scientists have studied these eclipses and explained to the world how these happens.
Types of Eclipses
On Earth we normally observe two types of eclipses – Solar eclipse and Lunar eclipse. Depending on the position of the objects and also the timing of alignments these eclipses are either partial eclipses or total eclipses .
Solar eclipse occurs when the sun is partially or completely hidden. See the
above image to understand how solar eclipse happens. In the above image you can see that the moon is moving around the earth in its orbit. While moving along its orbit, when the moon comes between the earth and the sun, it blocks the light of the sun from reaching the earth and the shadow of the moon falls on the earth. This phenomenon is called solar eclipse.
During solar eclipse two types of shadows of the moon falls on the earth. The first shadow is called the umbra and the second shadow is called the penumbra.
Umbra is the dark centre of the moon’s shadow and gets smaller as it reaches the earth (see the above image). People in the area of umbra see a total solar eclipse. During a total solar eclipse the sun, the moon and the earth lie in a perfect straight line. A total solar eclipse can also be seen from a small part of the earth. During total solar eclipse the sky becomes very dark as night.
People in the area of penumbra see a partial solar eclipse (see the above image). Partial solar eclipse occurs when the sun, the moon and the earth are not in exactly a straight line.
Some Interesting Facts on Solar Eclipse
- There are between 2 and 5 solar eclipses every year.
- A total solar eclipse can happen once every 1-2 years.
- The longest a total solar eclipse can last is 7 minutes and 50 seconds.
- We should never look at solar eclipse directly as it can damage our eyes permanently. We should use special equipment to see a solar eclipse.
Lunar eclipse occurs when the moon is partially or completely hidden. From the above image we can see that a lunar eclipse happens when the earth, while moving around its orbit around the sun, comes between the sun and the moon. The earth blocks the light of the sun from falling on the moon and shadow of the earth falls on the moon (see the above image). This phenomenon is called lunar eclipse.
When the moon and the sun are on opposite sides of the earth in a straight line, total lunar eclipse happens (see the above image). The moon look slightly reddish during a total lunar eclipse.
Partial lunar eclipse occurs when only a part of the moon come across into the earth’s shadow. The part of the moon which comes across the earth’s shadow appears very dark.
It is safe to look at a lunar eclipse directly.
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