Can books be included in literature reviews?
Note carefully the word scholarly in that description.  It refers to works whose intended audience is experts in the field, and which either present novel research or interpret existing results in a novel way.  Books can fit that description; often they will have been published by an academic publisher and reviewed for academic merit by expert editors or referees, prior to publication.  Scholarly books are sometimes called monographs, especially in the sciences.

The books you mentioned by Kaku and Sagan are not scholarly books.  They are intended for a non-expert popular audience, and they don't present new research or expand the state of the art.  The same goes for the online sources you listed; they are newspaper articles or blog posts intended for a popular audience.

A literature review is how you show that you are familiar with the state of the art.  It convinces the reader that they should believe you when you say that your proposed project is feasible, novel, and interesting.  You want to show that you are an expert, or are on your way to becoming one. Citing a popular book won't achieve that; it puts you at the same level as any random person interested in science who can read a bestseller list.