The topic of UFOs is indeed a mystery for those who believe and those who do not.  Short chapters tell of reports by people who have seen some and, at this point, not satisfactorily explained events.  The font is large and the photos and artwork of the occasions are thought provoking.  Words to know are defined on the page as well as in the glossary, which also has the phonetic pronunciation.  Some pages contain additional facts in “!” boxes.  The book becomes confusing on the last pages of chapter 4.  Some of the statements are misleading when presented as true or false statements.  One statement under False reads, “Many things are mistaken for UFOs.  Mistaken objects include sunlight reflection off ice crystals, birds’ wings, mirages, and marsh gas.”  This statement bewilders me.   Without the last chapter, this book is  informative for those wanting to read about observations of unexplained flying objects.