Some 70 percent of all stars in the universe are tiny red dwarfs, so faint and dim and seemingly humdrum that the casual observer might think stellar physics suffers from a lack of imagination.
But the “average star” belies the true breadth and sheer weirdness of the universe’s stellar catalogue. Stars in the universe range from extraordinary hypergiants to stars so small they look more like gas giant planets than burning balls of hydrogen. Some stars move so fast that they may leave their galaxies entirely, while theoretical stars may exist that stretch the boundaries of known physics.
From this panoply of stellar extremism we’ve chosen five examples that give you a taste of just how distinct and unique many classes of stars can be.
The Big Ones
The red hypergiant star UY Scuti is the largest star known. It has a radius about 1,700 times larger than the sun's. For comparison, the sun has a radius about 110 times that of Earth.