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- Can UV light make us invisible? 6 answers
The hottest stars have surface temperatures in the range of 40,000K. Wolfram Alpha says that such a star acting as a black body should radiate almost no energy in the visible spectrum.
Why then do such stars appear blue? I know the composition of elements in a star can affect its color via absorption lines, but I don't see how that would affect actual radiated light. And it doesn't seem that even these large stars are large or fast enough to red-shift their output by such a large amount.
Why aren't these stars invisible? As we don't seem to observe it, is there a reason that it is not possible for a star that is hot enough to radiate mostly in ultra-violet?