Eclipse 

An eclipse is a phenomenon of the universe where one celestial body passes into the shadow of another, blocking or obscuring its light. Eclipses are possible when the Sun, Moon, and Earth align themselves in space.

1.0Basics of Eclipse 

An eclipse is an astronomical occurrence when one celestial body eclipses another, thereby dimming its light. Generally, there are two classifications: solar eclipses, where the moon eclipses the sun, and lunar eclipses, where the earth obstructs the sun's light coming to the moon. 

2.0Types of Eclipse 

Solar and Lunar Eclipse are the two types of Eclipse that are seen on the Earth. Eclipse Solar lunar are further divided into sub-categories as follows: 

Solar Eclipse

A Solar Eclipse is observed when the Moon's position is in between the Earth and the Sun, blocking the light from the Sun from reaching the Earth. Example: Eclipse of the Sun 2024 occurred on April 8, 2024, visible across the areas of North America. There are several types of solar eclipses:

• Total Solar Eclipse: This kind of solar eclipse can be noticed when the Moon completely covers the Sun's disk, casting its shadow on Earth. It only occurs during a new moon phase just when the Sun, Moon, & Earth align themselves.
• Partial Solar Eclipse: It is when only part of the Sun is eclipsed by the Moon. That happens when the alignment is not perfect.
• Annular Solar Eclipse: This type of eclipse occurs when the moon is too far away from Earth to completely cover the sun, thus leaving a ring-like structure known as a "ring of fire." It occurs when the apparent size (with respect to Earth) of the moon is smaller than the sun.

Lunar Eclipse

A lunar eclipse is observed when the Earth comes in between the Sun and the Moon, casting a shadow of the Earth on the Moon. There are three types of lunar eclipses:

• Total Lunar Eclipse: It occurs when the Earth fully blocks the Sun's light from reaching the Moon. The Moon usually turns red because of the scattering of light through Earth's atmosphere, which is referred to as the "blood moon".
• Partial Lunar Eclipse: A partial lunar eclipse occurs when the Earth passes between the Sun and the Moon but only partially blocks the light of the Sun. It results in a portion of the Moon darkening while the rest is bright, which is quite contrasting.
• Penumbral Lunar Eclipse: In the eclipse penumbral, the Earth's penumbral shadow falls on the Moon, creating an extremely subtle lunar eclipse in which the light coming to the Moon through Earth is just reduced, rather than eclipsed.

3.0Types of Shadows 

Shadows are areas of shadow in which light is at least partially, and even totally obscured, by the celestial body. The Earth’s and Moon’s Shadows are divided into three regions: 

• Umbra: It is the innermost and darkest part of a shadow where light completely does not pass. For Example: Consider a total solar eclipse, The moon will cast its umbra on Earth. People within this region will experience the full obstruction of the sun, which makes the sky appear dark like the night sky. 

• Penumbra: The outer part of the shadow, but lighter as it is partially covered by the light source. For Example, during a partial solar eclipse, the people on Earth who are in the penumbra of the Moon's shadow will see the Sun partly covered. The Sun will appear as if it has been "bitten" or partially covered by the Moon but not fully covered.

• Antumbra: When it comes to an annular solar eclipse, this area is the place where a ring of the Sun remains visible around the Moon, as observed by an observer. For Example: In an annular solar eclipse, in which the moon remains farther away from the Earth and doesn’t completely cover the Sun. People in this region will see the Sun as a bright ring with the moon appearing smaller in the centre like two concentric circles. 

4.0Eclipse Cycle And Duration 

Eclipses are periodic events that follow a cycle known as the Saros cycle. This cycle is approximately 18 years, 11 days, and 8 hours long. The Sun, Earth, and Moon will have returned to roughly the same relative positions in their orbits after this period, and similar eclipses can be expected.

• A total solar eclipse usually lasts for a few minutes, typically between 3 to 7 minutes.
• A total lunar eclipse can take several hours, and the whole event occurs over 6 hours or more.

5.0Conditions for Eclipses 

Eclipses are caused by the relative position and size of the Sun, Moon, and Earth. For an eclipse to occur:

• Solar Eclipse: The Moon must be in the new moon phase and between the Earth and the Sun.
• Lunar Eclipse: The Moon should be at the full moon stage, and the Earth must be placed between the Sun and the Moon.

However, not all new or full moons create an eclipse because the orbits of Earth and Moon are inclined to each other by approximately 5 degrees. Eclipses only occur when the orbit of the Moon crosses the line joining the Earth and the Sun at places called nodes.

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