Interplanetary travel has always fascinated the human mind, specifically the exploration of new environments to understand their habitability and whether they have hosted life in the past or present. The main purpose of the following paper is to provide an overview of a mission to the planet Mars. Initially, an overview of the possible forms of energy, thanks to which a spacecraft can be powered, is shown, and subsequently, the production of energy using Radioisotope Thermoelectric Generators (RTGs) is focused on, since for interplanetary missions and deep space missions far from the Sun, it is not efficient to design a power system based on solar energy due to the weakness of solar radiation.