Blue colours in the cosmos usually refer to extreme heat and force - Magnetar is the ultimate light blue. So rare that even amongst the myriad stars in our galaxy, we have found only a handful of them.
A magnetar is born of only the mightiest of stars. After exhausting all its fuel, it is crushed into a tiny neutron star. They are about 20 kilometres across, yet they weigh more than our Sun. This is a recipe for density so impossibly high that they have a power of more than a hundred-trillion refrigerator magnets. Moreover, magnetars are so magnetic that they could tear apart - at the atomic level - any space traveller who might venture too close.
These Magnetic blue earrings are only for the rarest of individuals, to whom a plain old regular star is not significant enough.