Answer:
people with a casual interest in astronomy
Step-by-step explanation:
In "Great Astronomers," the author Robert Stewall Ball provides biographical information about specific astronomers and their discoveries. In fact, he focuses on the history of philosophers and astronomers, such as Ptolemy, Copernicus, and other modern astronomers. Finally, because its simplified content and language, as well as the fact that the passage does not mention the book is intended for scientists only, it is inferred that it is written for readers who are curious about astronomy.