Question: are there bigger planets then the sun?

Connor Macrae answered on 21 Jun 2015:

No there are not – thing is if a planet large enough does form, it will become a star! Think of Jupiter, our solar systems biggest planet. It’s chemical make up is not too far from the Sun, containing mostly Hydrogen. If Jupiter formed larger than it did, then the weight of the extra material pushing down on the core would make it hot enough to begin fusion, this is what drives the sun!