Planets

What are planets? 

Planets are circular objects that orbit a  star and it needs a core.

Exo planets

Exo planets are planets out of our solar system {a group of planets that orbit the Sun} .

How many planets there are in the Solar system

 There are nine planets Mercury Venus  Earth Mars Jupiter Saturn Uranus Neptune Pluto.

How many planets are there in the universe ?

We don 't know it but I think 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000666666666666666666666666666666666666.