We explain to you what a solar eclipse is and why this phenomenon occurs. In addition, types of solar eclipse and precautions to see one.
What is a solar eclipse?
A solar eclipse is a phenomenon in which the Moon interposes between the Sun and the Earth, and can hide it in a total, partial or annul way depending on of the size, the location and distance between the stars.
On average, an eclipse of the Sun occurs every 18 months and lasts only a few minutes . The same total solar eclipse takes 400 years to repeat itself in the same place on the planet. This occurs because, like the movement of the Earth around the Sun, the Moon also moves over its `` orbit '' or the optical one, but around our planet.
When drawing an imaginary line describing the translational movement of the celestial bodies, it is seen that the path of the orbit is oval. Therefore, depending on the section of the route, the Moon is closer or farther from Earth and these two in turn, more or less close to the Sun. This is the reason why they don't always line up in the same way or at the same time of the year .
See also: Earth transfer.
Why does a solar eclipse occur?
The movements of translation of the Earth and its natural satellite (the Moon), imply variations in the intensity of the shadow cast by the Moon on the planet at the time of the solar eclipse. The closer the Earth's Moon is, the more intense and smaller in diameter its shadow is. Thus the concealment of the Sun occurs, that is, a total eclipse is visible only from the area where the shadow is cast . From other nearby regions, where it reaches only the penumbra of the Moon, the same phenomenon is perceived as a partial solar eclipse.
To check this phenomenon in a simple way you can hold a ball between a lamp and a wall. As the ball approaches the lamp, the shadow it casts on the wall is bigger and softer. As the ball approaches the wall, the shadow has a smaller diameter and is more intense.
If the ball were the Moon, the wall the planet and the lamp the Sun, moving the ball can simulate the different instances of eclipses of the Sun.
Types of solar eclipse
- Total eclipse. It can be seen only from a certain area of the planet, in the center of the shadow cast by the Moon on Earth. From there, you can observe the total hiding of the luminous star.
- Partial eclipse. There is a partial concealment of the Sun and it can be seen from the twilight zone of the Earth, generated by the shadow of the Moon. You can see the luminous star partially hidden and, at the same time, appreciate part of its luminosity in the form of a half moon.
- Annular Eclipse Unlike the partial eclipse, due to the distance between the Moon and the Earth, the satellite does not generate a shadow that completely conceals the Sun but rather allows you to see a ring of light around it.
Precautions to observe a solar eclipse
You should never observe a solar eclipse directly .
While it is a natural phenomenon, it is important to take precautions as the direct and long-term observation of the Sun, on a normal day or during an eclipse, it can cause retinal burns and even permanent blindness. Radiations that emanate are very strong, capable of damaging sight in a very short time, especially in the smallest.
There are eyes designed to see an eclipse, whose crystals are similar in characteristics to those of the masks and weld. Despite seeing it through special glasses, it is not recommended to do it for more than 30 seconds in a row. The sunglasses we wear every day do not protect in these cases.
A lunar eclipse occurs when the Earth interposes between the Sun and the Moon, leaving the latter dark, totally or partially, without receiving the light from the luminous star.
The lunar eclipse can be seen in all terrestrial regions from where the satellite is visible, while the total sun eclipse can only be seen from the area of the Earth where the moon casts its shadow. from 30 minutes to a time, unlike the solar eclipse, which lasts only a few minutes.
More in: Lunar eclipse.