Anatomy Of The Sun

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Sun
        Birth of the Sun
        Some Interesting Points
        Anatomy of the Sun
                Core
                Radiation Zone
                Convection Zone
                Photosphere
                Chromosphere
                Corona
        Sunspots

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Sun is the star due to which we are present. It is our ultimate source of life and has given energy to us since we were born. The Sun is the largest and the brightest object in the solar system. It is the center of the solar system and is also called the heart of the solar system.

Sun

The Sun is a huge ball of extremely hot gas, mainly Hydrogen (about 70%), Helium (about 22-26%), other elements like Lithium, Carbon, Oxygen and some other heavy elements including Iron (but heavier elements are not in much amount).

The Sun is the center of our Solar system. Our Earth and other 7 planets revolve around it. Earth's mean distance from the sun is about 1 AU i.e 149,598,500 kms.

"Sun has 99.97% of the total mass of our solar system."

Birth of the Sun

As per the research and observations of various scientists and geologists, one clue came out that our Sun and the entire solar system was born in the nebula of a star that exploded about 5-6 billion years ago.

By accumulation of gases and dust of that nebula due to gravity that is becoming stronger and stronger as it gets more matter. This process for the generation of a proto-star was going on for millions of years and along the way the formation of an accretion disk took place that later helped a lot in the formation of planets that include our beautiful Earth also!

Once the pressure and thermal energy inside the proto-Sun has reached its extreme, then the fusion reaction starts between the two lightest elements i.e Hydrogen known as hydrogen fusion, in which a heavy nuclei of Helium atoms and a lot of energy is released.

"Now the actual birth of Sun takes place."

Some Interesting Points

• Our Galaxy milky way is about 32,000 light years away from our Sun. Basically it is the distance of our star 'Sun' from the center of 'milky way' which is a supermassive black hole named 'Sagittarius A'.
• The Sun is revolving around 'Sagittarius A' or our Galaxy 'Milky Way' nearly with a speed of 250 km per second.
• The frequency or period of revolution of the Sun around the center of our galaxy is nearly about 25 crore years.
• The Sun is made up of a gaseous system and this system is leveled at various layers that revolve at different speeds/velocities.
• The central part of the Sun completes one rotation about its axis nearly in 25 days, but on the other side the Polar part takes 35 days.
• Core temperature of the Sun is 1,50,00,000 degree Celsius.
• Diameter:- 110 times of the Earth.
• Density of the Sun is 1.41 grams per cubic centimeter.
• Relative mass of the Sun is 3,32,776 times that of Earth.

Anatomy of the Sun

As per the official data from NASA, European Space Agency and other space agencies and and scientists, there are various different layers that have different temperature, density, radiation, pressure and many other factors of classification, the Sun's layers are divided into the following:

1. Core.
2. Radiation Zone.
3. Convection Zone.
4. Photosphere.
5. Chromosphere.
6. Corona.

Core

"Core is the heart of the Sun."

Core is the innermost layer of the Sun (in fact Core refers to the innermost position), it is the place where fusion reactions between two Hydrogen atoms occur, actually it is the nuclear reactor of Sun or of any star. A very tremendous amount of energy is released in the fusion reaction and it goes into the outer space by crossing the other main layer or zones i.e. Radiation Zone, Convection Zone, Photosphere.

Radiation Zone

It is nearly the spherical zone above the Core, but not as dense as the Core. It could be the convection zone but it is still so dense due to which convection (movement of energy with matter as a host) cannot occur, hence named as Radiation zone.

The photons that are emitted at core pass through this zone, but since this zone is very dense the photon is continuously absorbed by atoms of this zone and are clicked in any direction and hence it helps to be a hurdle for photons. As per the official data, it's about 2 million degree Celsius at the upper end of this zone and about 7 million degree Celsius at lower.

Convection Zone

It is about 200,000 kms deep between the upper Photosphere and lower Radiation zone. At its upper zone, the temperature is nearly same as of Photosphere i.e. 4500-6000 *C and at deeper end the temperature is about 2 million degrees Celsius.

Photosphere

This is the outermost layer/region of the Sun that is 'visible'. This is about several 100 kms and almost all the radiation is emitted by this layer. The temperature of this layer varies between 4500 to 6000 *C. It is like the last step of success for a photon, after crossing it the photon will enter the vast Universe and will travel endlessly.

The Chromosphere and Corona are the two major outer atmospheres of the Sun.

Chromosphere

This layer is just above the Photosphere and here the density of Plasma goes down dramatically. This layer is about 1000 to 2000 kms thick but Spires of chromospheric gas can go up to 100,000 kms.

Chromosphere is basically the least dense zone in the atmosphere of the sun, sometimes called a vacuum.

Corona

This is the outermost layer of the Sun. It goes to a very high extent in the atmosphere of the Sun and emits X-rays.

This part of the Sun is basically cannot be seen due to the scattering of sunlight that overshadows it, but during the special occasion of Solar Eclipse, this layer can be seen at the borders (never see it without high quality sunglasses).

Sunspots

Sunspots are the regions that are relatively cooler, about 1000 *C or more than their surrounding atmosphere. They are formed on Photosphere. Since the region is cooler and has a magnetic break they emit less photons and hence are observed as black regions. Time period of the sunspot is around 22 years in which in half 11 years, the spot increases and in the other 11 years it decreases.

In other words Sunspots are the regions on the photosphere where the intense magnetic loop is formed that prevents the gas inside it to interact with surrounding and thus gas becomes cooler than others.

Sunspots are regions of high magnetic field, they help in emitting UV radiation and other harmful rays and it also accelerates solar flares and solar winds, which affects the earth in many ways.

It is due to the Magnetic Storms of Sun on Earth due to which electrical appliances, radio signals and compasses do not work correctly.

One great thing is that, when solar winds or ionized particle wind flows from the Sun and interacts with the upper atmospheric layers of Earth, ionized particles react and give us a very beautiful scene called 'Auroras'.