Lunar eclipses throughout history have always been a phenomenon and it is something that has had the world stopping and looking in awe for thousands of years. Eclipses occur when the earth blocks the light from the sun, illuminating the moon to a red colour, a beautiful sight for the eye of the beholder. Along with the sight itself, in many countries there are legends and stories carried on with them, most word of mouth which have been passed down from generation to generation. In this account, we aim to examine just what a lunar eclipse is, the history of them, and examples of eclipses and predictions of future occurrences.
Lunar eclipses are involved with the reflection of light from the sun to the moon being restricted because the Earth acts as a block between them. As this happens, the Moon, the Sun and the Earth are perfectly aligned with each other and the lack of light being held hostage from the moon produces what is called a Lunar Eclipse. These can only happen when there is a full moon. When the Earth blocks the light from the sun to the moon, the colour of the moon changes to a reddish/orange because of the unintended sunlight still managing to reflect and ignite it. MSU Solar Physics Researcher Pete Martens states: "The reason is the same reason as why the sky is blue. The little bit of sunlight that reaches the moon is actually deflected by the earth's atmosphere. So the little bit of light that reaches the moon, is the red light that came through, and the blue light is thrown out.'' This is Professor Marten's defined explanation as to why the moon changes colour. Lunar eclipses must not be confused with solar eclipses as they involve the moon blocking the sun's light towards the Earth. Also unlike Solar eclipses, lunar ones do not require any protective eye-gear and are completely safe to observe. Lunar eclipses have 3 specific types which are; Penumbral, Partial and Total. The Penumbral Lunar Eclipse involves the moon moving through the Earth's Penumbra and is very difficult to observe. The Partial Lunar Eclipse is when only part of the moon moves through the Earth's Umbra and are extremely easy to witness. Finally The Total Lunar Eclipse is when the whole moon moves through the Earth's umbra and appears to be very illuminating whilst the moon is red.
Since 2000 BCE through 3000 CE, there have been 7,718 eclipses of the Moon which are both total and partial. The number of total lunar eclipses can occur from 0 to 3 per year. Partial eclipses happen more often and could occur around 6 to 7 times per year.
A way of keeping track of when Lunar Eclipses are about to happen is by referring to a prediction technique called 'The Saros Cycle' This helps show when the Eclipses occur and portrays a unique pattern of occurrences every 6585.32 days which is just over 18 years.
It is also important to recognises that, like many other things in history they come with traditions and stories attaches with them, for example in many eastern countries this is the case. One example of this is in China. In Chinese traditions they believed that the moon represented a mirror, so whenever there was a lunar eclipse they would bang on mirrors. Their reason for doing this was because they thought that a dragon swallowed the moon, and beating the mirrors would make the dragon cough and return the moon to the sky. China was one of the first countries to figure out what eclipses were. For example –although no records remain- it has been said that they kept records of eclipses, that it helped them to determine the length of the year and that stars appear in the day. Therefore showing that the chinese were forward thinking in this time. Therefore, it is clear that historal lunar activities and eclipses are vital to what we know today, and without the recording, it would be difficult for us to make futire predictions.
To conclude, lunar eclipses are an experience which have fascinated, scared and set people in awe for many centuries and will continue to do so until the end of time. From the science of what they actually are and the history of them, it helps us to understand them so much more and predict their occurrences well into the future. They are an amazing event which will always bring people together for its sightings for many years to come.
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