How to check eyesight with the help of stars? Detailed answer

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How to check eyesight with the help of stars? Detailed answer

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How to check eyesight with the help of stars?

There are many legends about Ursa Major and Ursa Minor. Here is one of them. Once upon a time, King Lycaon, who ruled the country of Arcadia, had a daughter named Callisto. Her beauty was so extraordinary that she risked competing with Hera, the goddess and wife of the almighty supreme god Zeus. The jealous Hera eventually got her revenge on Callisto by turning her into an ugly she-bear.

When the son of Callisto, young Arkad, returning from hunting, saw a wild beast at the door of his house, he nearly killed his mother. Zeus prevented this - he held Arkad's hand, and Callisto forever took him to heaven, turning into a beautiful constellation - Ursa Major. At the same time, Callisto's beloved dog was also turned into Ursa Minor. Arcade Zeus turned into the constellation Bootes, forever doomed to guard his mother in the sky. Ursa Major and Ursa Minor are non-setting constellations, most visible in the northern sky.

Next to the star Mizar (from the Arabic word for "horse") - the second, or middle, star in the handle of the Big Dipper - the star Alkor is barely noticeable (in Arabic it means "horseman", "rider"). You can check your eyesight using it: if you see the star Alcor with the naked eye, then you are fine with it.

Author: Cellarius E.Yu.

Random interesting fact from the Great Encyclopedia:

How long can a camel go without water?

Before the invention of automobiles and airplanes, there was only one way to cross the deserts of Asia and Africa: by camel. That is why the camel was called the "ship of the desert". Of all the adaptations that enable the camel to live and travel in the desert, the most important is the hump on its back. When the hump empties, it loses its shape and begins to hang from the camel's back in flabby folds. There are no bones in the hump, it is made up of fat and muscle.

The purpose of the hump is to serve as a kind of food storage. Many days before the start of the journey, the owner of the camel forces him to eat and drink as much as possible. The camel is eating off, and its fat hump, weighing about forty-five kilograms, sticks upright on its back. This store of fat can sustain a camel for several days if it cannot find food for itself along the way. On the road, a camel can also make do with its internal water supply.

Before starting the journey, the driver forces him to drink about fifty liters of water. He achieves this by giving the camel salt and making it very thirsty. A camel has three stomachs. In the first, he accumulates food while grazing to form a cud. The second stomach contains digestive juices, while the third stomach is where the gum is being digested. In the walls of the first two stomachs are pockets for the accumulation of water. Muscles keep these pockets closed when they are full. As soon as the camel needs water, these muscles open the pocket, releasing as much water as necessary, and close again.

So how long can a camel go without water? As you have already noticed, it does not do without water in the full sense of the word. There are cases when a person dying of thirst was sometimes forced to kill a camel in order to get precious water. If a camel walks slowly and his load is not very heavy, this water can last him for six or even ten days!

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