A B type star with 15.6 solar masses but only 0.04 solar radii surely is interesting. I always thought they were bigger than, say, a G type star.
I am no astrophysic guy but the star's density would come close to a White Dwarf anyway.
Conservation of angular momentum. If it gets smaller and doesn't shed mass in some fashion then it has to spin faster.
Just like when you stand on the edge leaning out as far as you can when your 6 year old is spinning the roundabout up to speed then pull yourself in and move to the middle as soon as they've jumped on and scare them as it gets really fast
well rather than the star type,,,i would assume the gravitational effect from the black hole in system would explain it ,,, seen a few of these myself. seeing a sun spin full circle in around 10 seconds is very eerie.
Sadly, I'm not convinced that the algorithm which generates stars in the game follows what is observed particularly accurately. A Type B main sequence star (which is what the description implies in the photo above) shouldn't have a radius less than about 2 solar radii. I've not been playing the game long but I've seen plenty of other examples where stars have a radius which makes no sense when compared with real world definitions. However, I can suspend my disbelief and enjoy it!
There are some oddities out there, but some do get cleaned up. A lot of ages were reworked with 1.3 to get rid of stars that were older than the universe, for example.