Celestial navigation is an ancient method of navigating using celestial bodies like stars, the sun, moon, and planets. Sailors use instruments like a sextant to measure angles between celestial objects and the horizon, allowing them to calculate their position on Earth. However, with the rise of GPS and electronic navigation systems, celestial navigation has become less popular.The main goal of the book is to reduce the dependence on GPS as the sole navigation method and minimize the risk of a single point failure. By leveraging available technology, celestial navigation can continue to play a significant role in ensuring safe passage for ships worldwide. The book explores the application of these modern technologies to address the challenges of ship navigation.