The biggest planet ever found is a gas giant named ROXs 42Bb, located about 460 light-years from Earth.
It is estimated to be about nine times the mass of Jupiter and has a radius of about 2.5 times that of Jupiter.
As you can see, ROXs 42Bb is a true giant among planets. It is so large that it is not even considered to be a planet by some astronomers, but rather a brown dwarf.
Brown dwarfs are objects that are too large to be planets but too small to be stars. They are not able to sustain nuclear fusion in their cores, which is what powers stars.
This is much younger than our own solar system, which is about 4.6 billion years old. It is possible that ROXs 42Bb is still contracting and could shrink in size over time.
The discovery of ROXs 42Bb is a reminder of the vastness of the universe and the many mysteries that still remain.