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Eyes: How They Work, Anatomy and Common Condition

 The eye is a complex sensory organ that allows us to see the world around us. The eye works by gathering light from the environment and converting it into electrical signals that can be interpreted by the brain. The basic structure of the eye includes the cornea, iris, pupil, lens, retina, and optic nerve. The cornea is the transparent outer layer of the eye that helps to focus incoming light. The iris is the colored part of the eye that regulates the amount of light that enters the eye through the pupil, which is the black circular opening in the center of the iris. The lens is a clear, flexible structure located behind the iris that helps to focus light onto the retina. The retina is a thin layer of tissue that lines the back of the eye and contains photoreceptor cells called rods and cones. These cells convert light into electrical signals that are sent to the brain via the optic nerve. The rods are responsible for the low light vision and detecting motion, while the cones are ...
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Origin of universe

                                 what is universe 

                                              & 

                             how it comes in existence?


The first question in our topic is what is universe, so let us talk about it. universe , it is a huge cluster of galaxies and these galaxies contains many stars and clouds of gases and dusts and all other forms  of matter and energy
So this is our universe.Now think what is the size of universe ? Its size is unimaginable , considering the size of universe, earth is indeed a speck i.e. The universe is too vast and its size is not limited it is expanding from the time of beginning of universe to presently with great speed in all direction. while it is possible to measure the size of observable universe, which is currently estimated to be 93 billion light years in diameter


Now let us talk about second question that how universe comes in existence so many scientists try to explain the existence of universe but the most acceptable theory of origin of universe  was Big Bang Theory. This theory was first suggested by a Belgian priest named Georges Lemaitre in 1920 .

Georges Lemaitre
17 July 1894 - 20 June 1966

This theory said us that around 20 billion years ago a single huge dense entity was formed with the matter present in space, and when this huge dense entity become too much unstable and contain an unimaginable amount of energy that will result in the huge single thermonuclear explosion which is unimaginable in physical terms, and this huge explosion is called big bang.

After that explosion the universe expanded and hence, the temperature came down.The gaseous clouds which were formed during explosion condensed under gravitation and converted into
many disc like structures called nebula, made up of atoms and small particles.Solar nebula was one of them, which formed our solar system and similarly many galaxies are formed.

The central part of solar nebula was become still hotter and converted into sun and due to condensation of atoms and dust particles moving around the sun other planets are formed and thus our planet also comes in existence.

So, this is the theory of origin of our universe hope you will like it because when we talk about universe nothing is as much interesting as this .Thanks for reading next post is coming soon with more interesting knowledge.

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