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Lunar Eclipse - Information and Features

A lunar eclipse (from the Latin eclipsis and from the Greek Εκλείψεις) is an astronomical event that happens when the Earth stands between the Sun and the Moon, generating a cone of shadow that obscures the Moon.

Image of earth passes directly between the Moon and the Sun, causing the Earth's shadow produced by the Sun's light to be cast onto the Moon.
A lunar eclipse is an astronomical phenomenon that occurs when the Earth passes directly between the Moon and the Sun, causing the Earth's shadow produced by the Sun's light to be cast onto the Moon. 

A lunar eclipse is an astronomical phenomenon that occurs when the Earth passes directly between the Moon and the Sun, causing the Earth's shadow produced by the Sun's light to be cast onto the Moon. 

For this to occur, it requires all three heavenly bodies to be in or near a position. This means that they are formed in a straight line.

The type and duration of a lunar eclipse depends on the position of the Moon in relation to its orbital nodes which are the points where the Moon's orbit crosses the plane of the Sun's orbit.

Image of the moon disappears completely, as the shadow of the earth covers it.

During a lunar eclipse, the Earth prevents sunlight from reaching the moon. That means that at night, the full moon disappears completely, as the shadow of the Earth covers it.
In order to know the types of lunar eclipse, one must understand the shadow that the Earth produces as a result of the illumination of the Sun. As our star is larger, it produces two types of shadow, one in the form of a darker cone called Umbra and is the part where the light is completely blocked while Penumbra is the part where only a portion of the light is blocked. As shown in the diagram.
Between 2 and 5 lunar eclipses occur each year.
In solar eclipses, the same three heavenly bodies are involved, but the difference between the two lies in the position of each of them. In a lunar eclipse, the Earth interposes itself between the Moon and the Sun, casting a shadow on the Moon, while in a solar eclipse, the Moon interposes itself between the Sun and the Earth, casting its shadow on a small part of the latter.

A person can watch a lunar eclipse from any area of the Earth where the satellite is visible from the horizon and during the night, while during a solar eclipse it is only seen for brief moments and in certain parts of the Earth.

Another difference with respect to eclipses of the Sun, is that a total Moon eclipse lasts on average from 30 minutes to 1 hour, but can be extended a few hours more. This is simply a result of the large size of the Earth compared to the smaller Moon. On the other hand, the Sun is much larger than the Earth and the Moon, which makes the phenomenon very brief.

Phases of the lunar eclipse.

Why does a lunar eclipse occur?

Between 2 and 7 lunar eclipses occur each year. Depending on the position of the Moon in relation to the Earth's shadow, three types of lunar eclipses occur, and although they are more frequent than solar eclipses, they do not occur every time there is a full Moon, since the following is required:

The Moon must be at full moon, that is, at full moon. That is, completely behind the Earth from the Sun.

The Earth must be physically located between the Sun and the Moon so that all the bodies are at the same time on the same plane of orbit, or very close to it. This is the main reason why they don't happen every month, since the Moon's orbit is tilted about 5 degrees from the ecliptic.

The Moon must pass completely or partially within the Earth's shadow.

What are the types of lunar eclipse?

Total lunar eclipse.

It occurs when the entire (entire) Moon passes through the Earth's shadow threshold. In other words, the Moon enters completely into the cone of the umbra. During the development and course of this type of eclipse, the Moon passes through the following sequence of eclipses: 1) penumbral, 2) partial, 3) total, 4) partial and 5) penumbral.

Partial lunar eclipse.

In this case, only a part of the Moon enters the threshold shadow of the Earth and therefore the other part is in the penumbral zone.

Penumbral lunar eclipse.

The Moon only passes through the area of darkness. It is the most difficult type to observe as the shadow on the Moon is quite subtle, precisely because the penumbra is a diffuse shadow. Additionally, a total penumbral eclipse is considered if the Moon is completely within the penumbral area, and a partial penumbral eclipse if only part of the Moon is within the penumbra and the other part is without any shadow.

Stages of a Total Lunar Eclipse

In a total lunar eclipse, a series of stages can be distinguished that are determined by the contact of the Moon with each of the shaded areas.

P1. The penumbral eclipse begins.
The Moon comes into contact with the outer part of the penumbra which means that from now on one part is inside the penumbra and the other part is outside.

U1. Beginning of the partial eclipse.
By definition, a partial eclipse is when the Moon has one part in the threshold zone and another in the penumbral zone, so when it contacts the threshold zone the partial eclipse begins.

U2. The total eclipse is beginning.
The Moon is completely within the threshold zone.

This stage occurs when the Moon is in the center of the umbra.

U3. End of the total eclipse.
When it comes into contact again with the other side of the penumbral zone, the total eclipse ends and a partial eclipse begins again, ending the total eclipse.

U4. End of the partial eclipse.
The Moon leaves the threshold zone completely to be completely in penumbra which indicates the end of the partial eclipse and the beginning again of a penumbral eclipse.

P4. End of the penumbral eclipse.
The Moon comes out of the penumbra completely, which implies the end of the penumbral eclipse and of the eclipse as a whole.

Types of lunar eclipse.

A story you didn't know. The Eclipse of 1504

It was the beginning of 1504 during Christopher Columbus' second voyage. He and his crew were in northern Jamaica where they were beginning to be viewed with suspicion by the natives who refused to continue to share their food with them, which put Columbus and his people in serious trouble.

Columbus had read in a scientific document of the time, which included the lunar cycles, that there would soon be an eclipse in the area and he took the opportunity. Wanting to show himself as superior to have influence on the Indians, he threatened them with making the moon disappear on the night of February 29, 1504. After seeing that he had made the Moon disappear, the natives begged him to return it to its original form, which he obviously did a few hours later when the eclipse was over.

In this way, Columbus managed to keep the natives sharing their food.

Red Moon or Blood Moon.

During total eclipses, the Moon turns red which gave it the popular name of Blood Moon. This phenomenon occurs because when it does not receive light from the Sun, the Moon only receives some refracted illumination in the Earth's atmosphere, which gives it this color, for exactly the same reason that it looks red at sunset.

The dramatic nature of this colour has generated a great deal of speculation and prophecy throughout history.

Solar eclipses in culture.

Both solar and lunar eclipses have amazed humans for millennia and each ancient culture gave them different explanations and created a mythology around them.

The Egyptians believed that a badger swallowed the moon temporarily; the Mayans thought it was a jaguar, while the Chinese believed it was a three-legged toad.

The Mesopotamians believed that the Moon was attacked by demons, and in other parts of China they thought it was dragons trying to devour the Moon.

The Incas, as well as the Mayans, thought that a jaguar attacked the moon and that is why its color was red. Rituals to scare away the beasts were practiced by most of these civilizations who feared losing the Moon forever every time one of these phenomena occurred.