Bug in Asimov's book.

I am now flying to Las Vegas to present some stuff on CES, and reading "Nemesis" by Isaac Asimov. He is one of my favourite hard sci-fi authors, and usually he is very careful, realistic and thorough in all references to astronomy, physics, etc.

However in "Nemesis" he managed to make a spectacular bug: One of the cornerstone's of the story is that a star to which some colonists immigrated from the earth is closer to us then Proxima Centauri but is not normally visible from inner solar system because of a dust cloud. However in a middle of the book main characters spend a lot of time watching the brightest star on their sky - our Sun.

I am only thinking if there is any chance that I miss something and this is not a bug?