“Mangalyaan was launched on November 5, 2013, to Mars by Indian Space Research Organization (ISRO). On October 2, 2022, ISRO declared that Mangalyaan had lost communications with Earth. Mars Color Camera (MCC) on-board Mangalyaan has taken thousands pictures of Mars. A full disk of Mars image observed by Viking is shown on the cover page of this book. Mars is covered by the dust as observed by Mangalyaan (from Arya et al., 2015).  This book presents the atmospheric and ionospheric results obtained from all missions to Mars. It also covers various atmospheric and ionospheric models of Mars. Broadly speaking, the planet atmosphere can be divided into two regions: lower and upper. These two regions can be coupled due to the propagation of energy from the lower to the upper atmosphere. The first-ever book on the aeronomy of Mars, this work is intended to help students and researchers familiarize themselves with the field of aeronomy. In addition, it helps planetary probe designers, engineers, and other users in the scientific community, e.g., planetary geologists and geophysicists�.