Eclipse – Facts and Myths
Eclipse was considered a bad omen from ancient times, but as time passed, the scientific development we achieve helps us better understand this phenomenon. It’s a simple phenomenon occurring similar to the shadow we create on the wall by blocking light. Still, the distance from the sun and the size of the moon affect how we view it, though as a lucky civilizations, we are fortunate enough to view total eclipses.
What is the eclipse?
Eclipse word derived from the Greek word ekleipsis, meaning ‘being abandoned. An eclipse occurs when a celestial body, such as the moon or planet, comes into the shadow of another celestial body. We can observe two types of eclipses from the earth – solar and lunar eclipses.
A solar eclipse occurs when the sun, moon, and earth are aligned perfectly. In other words, a solar eclipse occurs when the moon comes in between the sun and the earth. Even though the sun is 400 times larger than the moon, it is as much farther from the moon, so from the earth, both seem to be of the same size, and the moon appears to block the sunlight and cast a shadow.
A lunar eclipse occurs when the sun, earth and moon are aligned in a line. In other words when the earth casts a shadow on the moon.
What are the types of solar eclipses?
Solar eclipses are mainly of three types :
- Total eclipse: It occurs when for the observer the sun, moon and earth are perfectly aligned. It can only be visible for a small area on earth, the places in the centre of the moon’s shadow.
2. Partial eclipse: When the sun, moon and earth are not perfectly aligned for the observer, still some parts will be covered by the moon.
3. Annular eclipse: When the moon is farther away from earth it seems smaller and it will not completely cover, will look like a dark disc on top of a larger disc.
During a solar eclipse, the moon casts two types of shadow
- Umbra: It’s the smaller shadow and people standing within the umbra can see a total solar eclipse
- Penumbra: The wider shadow cast by the moon and people standing within the penumbra will see a partial eclipse.
What are the myths about the eclipse and what are the facts behind it?
Ancient Greeks and Chinese people believed eclipses were a bad omen and they believed it happens when their good is angry at them. Some societies believed the lunar eclipse occurs due to a demon swallowing the moon. Even the word symbolises these beliefs and myths. Still, people have misconceptions like going outside during an eclipse is harmful and so on. Looking directly at the sun during an eclipse is harmful to the eyes. Even after knowing the scientific reasons the ancient people used the myths to spread fear. One such incident is, in 1504 Christopher Columbus and his crew were camped in Jamaica and after some time the native people stopped the supply of food, so he used his scientific knowledge and predicted the lunar eclipse on march 1504. When it happened he feared the people by saying his god is angry with them because of their mistreatment.
Do other planets also experience eclipses? Will we continue to experience an eclipse?
Yes, other planets also have eclipses but yeah the view will be different from what we experience from the earth. The mars eclipse was recorded by the mars perseverance rover was completely different to our experience. Mars’s moon being small, the total eclipse will not occur on mars. Mercury and venus will not experience an eclipse as they don’t have any moons. Gas giants and ice giants also experience an eclipse but the occurrence interval and time period are so different. On earth, after around 600 million years we will no longer experience an eclipse. The moon is moving away from the earth around 1.6 inches each year so due to tides, and the slowing down of the earth’s rotation, the moon moving away from the earth will bring an end to solar eclipses. Now, we will continue to witness at least 2 solar eclipses per year somewhere from the earth.
What did the 1919 historic eclipse all about?
Einstein’s general theory of relativity explains the concept of gravity as the distortion of space-time by masses. It predicted the curvature of space-time can bend light but to witness this we need bodies of heavier mass. So if this is true the light should bend around the sun, but due to the brighter light, this can only be calculated only during an eclipse. So on the eclipse that happened on 29 May 1919 the great British astronomer Arthur Eddington travel to the island off the coast of Africa to observe the total eclipse and to verify light deflected in gravitational fields. Edington photographed the star in the vicinity of the sun and observed that the position of these stars is slightly shifted from the original position. Hence Einstein’s theory proved. This was considered a historic event in history.