Overview[]
HD 100546 B is the largest real exoplanet in terms of radius that has been discovered to date. It orbits the star HD 100546 (also known as KR Muscae) 353 light-years away from Earth.[1] The planet is on the younger side of things with it being in the planet formation phase of the planetary life cycle. The gas giant was first thought to be around 6.9 Jupiter radii, but other, more recent estimates put it at 3.4 Jupiter radii, which still makes it the largest exoplanet known by far.[2] The 6.9 Jupiter radii estimate is still used in SpaceEngine. There are no confirmed moons around this planet. It was discovered by an unnamed group of researchers in 2013, and was announced in 2014. Below is a comparison of this planet to others in our Solar System.
The planet has several estimates about the mass of it, with NASA suggesting its ~8.6M♃, along with some other various sources stating its in the range of 4 - 13 M♃. This is why there is no definitive mass of the planet.
In SpaceEngine, HD 100546 B is so large, oblate enough, and has so little density that the surface gravity is negative in certain areas.
