This book introduces readers to famous UFO sightings, revealing what the legends claim, some possible explanations, and what people still don’t know for sure. Short paragraphs of easy—to—read text are paired with eye—catching images to make reading engaging and accessible. The book also includes a table of contents, fun facts, sidebars, comprehension questions, a glossary, an index, and a list of resources for further reading. Apex books have low reading levels (grades 2—3) but are designed for older students, with interest levels of grades 3—7.