When I first saw the illustration at left of the sun-like star that has comets orbiting it, I thought that the star looked as red as a carbon star. At right you can see an example of a carbon star, T Lyrae. Its color varies, but may be as red B-V = +5.5. HD 161327, on the other hand, belongs to spectral class F5 and has a B-V index of +0.48. The difference is huge.
If HD 181327 had been as red as T Lyrae, there would be no way that its system of comets, illuminated by the light of their sun, would look blue.
I realize that many people are terribly tired of my ever-recurring complaints about the color of astronomical images, and I realize that I'm sensitive to such things bordering on the hysterical. At least I can accept that mapped color images of phenomena emitting their energy at wavelengths outside the visual spectrum can never be "realistically colorized". So in such instances, complaining about the colors of an out-of-the-visual-spectrum image is like griping that the portrait of an atom doesn't make it look like the Solar system. Yeah, right.
But when it comes to the illustration of HD 181327, there is no reason why this should be seen as "mapped color". Instead, the picture flatters the public misunderstanding that hot sources like stars should look red, and cold sources like ice should look blue.
At the very, very least, the picture could have shown HD 181327 looking yellowish, like in this (rather red)
zimmer.csufresno.edu portrait of
F5-type star Mirfak.
Ann