me wrote:
Hi

Sirius B, a white dwarf, has a surface temperature of around 25,000 degrees
C. Sirius A, a blue/white main sequence star has a surface temperature of
around 12,000 degrees C. Usually the bluer a star is, the hotter it is. Just
wondered why it's not the case here.


A very nice web site where you can study the color of stars is the Sloan
Digital Sky Survey site: http://cas.sdss.org/dr3/en/proj/advanced/color/