Ariana sun and stars

The sun is in the center of the solar system.

the first layer is the middle layer called the radiation zone. 

the outer layer is called convection zone it helps move heat from the core to the surface 

the visible surface is called the photosphere 

this surrounds the photosphere

heat and light energy are produced by nuclear reactions with in the sun 

the cloud of gas surrounding the outermost layer is called the corona 

the surface temperature of the sun is nearly 5500 degrease while the temperature of the core reaches 15,000,000 degrease. 

all stars seen without a telescope belong to the Milky Way Galaxy. 

the brightest star in the sky is Sirius, the dog star, 8.8 light years away. 

Sirius is of the first magnitude a designation on indicating the brightness of a star. 

A light  year is the distance light travels in a light year about 9.6 trillion km Betelgeuse a giant red star is 200light years away. 

the north star, polar is a pulsating variable with a period of about four days. 

a nova star is a star that suddenly increases in brightness and later returns to its original magnitude.