The solar system is born when the formation of the sun begin which was around 5
billion years ago. Astronomical Object can be separated in to 4 part, inner planets, asteroid belt,
outer planets, and comet or Oort’s cloud from the sun to outer space respectively. Planets in
solar system must have 3 characteristics 1) orbiting around the sun, 2) shape is stable due to its
own gravity and 3)has cleared the neighborhood around its orbit. Planets can be classified in to
2 types, rocky planets, Solid surface with metallic Core, and gas planets, liquid or no surface
with stone or ice core. The sun has about 7 layer of structure and atmosphere, while the core,
where nuclease fusion occur, is around 15 million degrees Celsius, the hottest layer is believed
to be the Corona, the outer part of the sun’s atmosphere, at 20 million degrees Celsius.