The contributed chapter, “Science of the Moon” by Jennifer Edmunson (ST23) and Heidi Haviland (ST13) for the book, “Handbook of Lunar Base Design and Development”, edited by P. Eckart and A. Aldrin, has been published. https://doi.org/10.1007/978-3-030-05323-9_20-2. This book chapter discusses an overview of the present state of knowledge of the Moon and the important open scientific questions. We provide a brief history and geology of the Moon, properties of the regolith, and effects of radiation at the surface. Lunar surface volatile processes are discussed within permanently shadowed regions. A list of instruments is provided as example of future missions needed to address these open science questions.