The Sun and its Energy

Sun and its energy

The Sun is the center of our Solar System, and it provides energy for life on Earth, which is significant for us. Here I have a blog for you to learn some things about the structure of the Sun and its radiation transport.

https://www.cliffsnotes.com/study-guides/astronomy/the-sun-a-representative-star/properties-of-the-sun

The structure of the Sun/Radiation transport within the Sun

https://www.youtube.com/watch?v=bLnTwHCKs18

Core: Solar energy is produced at the center of the Sun, where temperatures reach 15 *10^6 K. The core is a significant zone that we need to pay more attention about it. It is in the core that nuclear fusion takes place. Nuclear fusion is a process that four hydrogen nuclei combine into one helium nucleus and release enormous amounts of energy described as Einstein's equation E=mc^2

Radiative Zone: Energy from the core slowly rises in the Radiative Zone. In this zone, the energy is transported by the photons from core to the convection zone. In this process, the photons travel at the speed of light. The paths they take through the Radiative Zone zigzag so much that This process will take about 170 thousand years. 
As the zone is very hot, the photons and electrons will be separated. And during the way out, the photons bounce into the free electrons and change directions for many times, that is the reason why it takes so long time for the photons to get out.

Here is a video that describes the process of energy's travel in the Radiative Zone.

https://www.youtube.com/watch?v=cGY8L8cb-g0

Convection Zone: At the bottom of Convection Zone, the solar plasma absorbs photons. This absorption makes it become ready to convect. In the convection process, the energy is transported upward by rising hot plasma. We know that the hotter gas has relatively lower density while the cool gas have relatively higher density. This difference in density makes it possible for the plasma to rise.

http://ircamera.as.arizona.edu/NatSci102/NatSci102/lectures/suninterior.htm

Here is a video with an experiment that describes the process of energy's travel in the Convection Zone.

https://www.youtube.com/watch?v=6w8u9YzZXNM

Photosphere: The Photosphere is the visible surface of the Sun, where the temperature is about 6000 K. This is the part that gives off light that we can see from here on Earth.

Chromosphere: The chromosphere is a thin layer of gas above the photosphere. The temperature at the surface of Chromosphere is about 4,300K while the temperature at the top of the Chromosphere can reach more than 10,000 K. This suddenly increase of temperature is a very odd behavior of the Sun.

Corona: The Corona's a gas layer above the Chromosphere and it is just as thin as the Chromosphere. The Corona is the outmost layer of the sun and extends about 1.8 Sun's radius from Chromosphere.  The temperature of Corona is 1,000,000 K. It is invisible for most times, but it is visible during a total solar eclipse when the Sun's surface is completely hidden by the Moon. here is a picture of solar eclipse.

https://en.wikipedia.org/wiki/Solar_eclipse

Solar Wind: The solar wind is the stream of charged particles, or plasma, released from the upper atmosphere of the sun. When charged particles from the sun are blown to the atmosphere of the sun, they will cause the electrons in the atoms to move to a higher-energy state. And when the electrons drop back to the low-energy state,  they will release photons, in the other word, light. This process produces beautiful aurora. The solar wind was very powerful in the past compare with today's. In the past after the juvian lanets just formed,  the solar wind was so powerful that it was able to blow away the gaseous compnents of the solar nubela.

Sources:

http://futurism.com/how-the-sun-works/
http://earthsky.org/earth/what-causes-the-aurora-borealis-or-northern-lights